A-C-Unit Guides 3/Unit F.pdfTitle: A-C-Unit Guides.qxd Author: ganesan Created Date: 6/25/2004 11:27:16 AM

Sheet 1 of 1© Harcourt Education Ltd 2004 Catalyst 3This worksheet may have been altered from the original on the CD-ROM.

F Unit guidePatterns of reactivityWhere this unit fits in Prior learningThis unit builds on:unit 8E Atoms and elements, unit 8F Compounds and mixtures and unit 9E Reactions of metals and metal compounds.Ideas in this unit are developed further in 9G Environmental chemistry and 9H Using chemistry.

The concepts in this unit are: different metals show similar reactions but the rate of reaction varies; metals can be arranged in order of reactivity – the reactivity series is a very useful tool for understanding and predicting metal reactions.

This unit leads onto: work in key stage 4 on metals and their compounds.

This unit relates to: unit 9E Reactions of metals and metal compounds.

To make good progress, pupils startingthis unit need to:• be able to explain the differences

between elements and compounds• have represented elements and

compounds by symbols and formulae• have represented chemical reactions by

word questions• know that many metals react with

oxygen to form oxides• be able to make generalisations about

the reaction of metals with acids.

Framework yearly teaching objectives – Particles• Identify evidence which indicates that a chemical reaction has taken place, such as the association of energy transfer with chemical change.• Recognise that chemical reactions can be modelled by assuming that atoms can rearrange themselves, and that this can happen in only a limited

number of ways, for example: A + B→ AB, AB + CD → AD + CB.• Use the particle rearrangement model to: predict the names and formulae for products that might be formed from given reactants; write word and

symbol equations for some simple reactions.• Identify differences in reactivity of metals to construct a reactivity series; use this to explain uses of metals and make predictions about the

reactions of metals.

Expectations from the QCA Scheme of Work At the end of this unit …

… most pupils will … … some pupils will not have made somuch progress and will …

… some pupils will have progressedfurther and will …

in terms of scientific enquiry NC Programme of Study Sc1 2b, c, d, e, f, g, h, i, j, m, o

• select and make effective use of secondary sourcesabout the origins and uses of metals

• identify relevant observations and describe patternsin these

• suggest a workable approach to investigating thereaction of metals with acids, identifying variablesto be controlled

• explain results using scientific knowledge andunderstanding.

• select information from secondary sourcesabout the origins and uses of metals

• describe observations and identify wherethere are similarities

• suggest how reaction with acids might beinvestigated, controlling variablesidentified for them

• relate results to scientific knowledge andunderstanding.

• synthesise information from secondarysources

• point out where reactions do not fit thepattern expected.

in terms of materials and their properties NC Programme of Study Sc3 1d, 3a, b, c, d, h

• identify and describe similarities in chemicalreactions

• identify differences in the reactivity of differentmetals and use these to explain some everyday usesand occurrence of metals

• represent chemical reactions by word equations.

• describe how some metals react with water,acids and oxygen

• give some uses of metals, relating these tothe reactivity of the metal.

• use the reactivity series to make predictionsabout the reactions of metals

• relate the reactivity of a metal to its uses,how it occurs and when it was firstextracted and used

• represent some reactions by symbol equations.

Suggested lesson allocation (see individual lesson planning guides)Direct route

F1Losing thatshine

F2Corrosive liquids

F3Changing places

F4Who’s top of theleague?

F5Reactivityin action

F6Variables together – Thinkabout variables that interact

Booster 4Focus on particles 2 –Chemical changes

Extra lessons (not in Pupil book)

Review and assessprogress (distributedappropriately)

MisconceptionsPupils often think that a faster reaction produces more product rather than simply getting to the same end point sooner.

Additional informationThe anomalous position of aluminium has not been introduced in this unit.

Health and safety (see activity notes to inform risk assessment)Risk assessments are required for any hazardous activity. In this unit pupils observe reactions of alkali metals, use metals, acids and solutions ofsalts which may be hazardous and also use flammable metals and observe what happens when they burn. They observe the thermit reaction, workwith coarse mesh filings of metals and plan and carry out their own investigation into the reaction of metals with acids.

D-F-Unit Guides.qxd 16-Jun-04 3:08 PM Page 14


F1Lesson planning

guideLosing that shine

Suggested alternative starter activities (5–10 minutes)

Introduce the unit

Unit map for Patterns ofreactivity.

Learning outcomes

Share learningobjectives

• Describe what happenswhen metals corrode.

• Explain patterns in theway metal objects corrode.(Sc1)

Brainstorming

Pupils consider the life of an iron bridge. Catalyst InteractivePresentations 3

Capture interest (1)

Show pupils fake goldjewellery and discusswhether it will corrode.


Show photos of differentmetals and discuss howthey change over time.Catalyst InteractivePresentations 3

Suggested alternative plenary activities (5–10 minutes)

Review learning

Pupils make key fact cardsand use them to test eachother.

Sharing responses

Whole-class discussionsummarising ideas aboutwhat causes metals tocorrode at different rates.

Group feedback

Pupils combine into largergroups to compare theirresponses to Activity F1b.

Word game

Pupils complete sentenceswith missing words to showkey points of lesson.

Looking ahead

Pupils think about othersubstances that react withmetals using the context ofan iron bridge.Catalyst InteractivePresentations 3

Suggested alternative main activitiesActivity

Textbook F1

Activity F1a Practical

Activity F1b Paper

Activity F1c Paper

Learningobjectivessee above

i, ii and iii

i, ii and iii

i, ii, iii and v

iv

Description

Teacher-led explanation and questioning OR Pupils work individually,in pairs or in small groups through the in-text questions and thenonto the end-of-spread questions if time allows.

Reactive metals and oxygen Demonstration of reactions of morereactive metals with oxygen.

Tarnished metal Pupils answer questions about gold, iron andchromium corroding under different conditions.

Inside the atom The most able pupils are introduced to the conceptof atomic structure.

Approx. timing

20 min

10 min

20 min

15 min

Target group

C H E S

R/G G R S

✔

✔

✔

Key wordsoxide, reactive, unreactive, reactivity

Out-of-lesson learningHomework F1Textbook F1 end-of-spread questionsActivity F1bActivity F1c

Most pupils will ...

• appreciate that different metals react with oxygenat different rates

• link rate of reaction to reactivity• appreciate that more reactive metals release more

energy.

Some pupils, making less progress will ...

• recall the basic metal/oxygen reaction.

Some pupils, making more progresswill ...

• understand and apply the concept ofreactivity in a wider range of situations.

Learning objectivesi Find out what happens when metal reacts with oxygen.ii Metals react with oxygen at different rates and release different amounts of energy.iii Be able to write word equations for the reaction of metals with oxygen.iv Atoms contain electrons and protons. (extension only)

Scientific enquiryv Use information about the corrosion of metal objects to suggest patterns. (Framework YTO Sc1 9f)



F2Lesson planning

guideCorrosive liquids


Recap last lesson

Quick quiz in groups aboutmetals reacting with air.

Learning objectivesi Find out what happens when metal reacts with acid.ii Find out what happens when metal reacts with water.iii Metals react with acid and water at different rates.iv Electrons are arranged in shells round the nucleus of an atom. (extension only)

Scientific enquiryv Describe patterns in the reactivity of metals using experimental data. (Framework YTO Sc1 9f)vi Present observations using tables. (Framework YTO Sc1 9e)

Learning outcomes

Share learningobjectives

• Describe what happenswhen metals react withwater and acids.

• Predict how reactive ametal is from experimentalobservations. (Sc1)

Problem solving

Chemical changes in ablacksmith’s.

Brainstorming

Corrosion of coins intreasure chests.

Capture interest

Show a video clip ofreaction of group I metals,including rubidium andcaesium, with water. Catalyst InteractivePresentations 3


Review learning

True/false quiz.

Sharing responses

Pupils work in groups todiscuss the outcomes ofActivity F2b.

Group feedback

Whole group discussionrelating to safetyprecautions when workingwith metals and acids.

Word game

Play ‘What am I?’ to guessthe metal.

Looking ahead

Class discussion abouttrends in reactivity.


Textbook F2


Activity F2b Practical

Activity F2c ICT

Activity F2d Paper


i and ii

i, ii, iii, vand vi

i, iii and v

i and ii

iv

Description


Reacting metals with water Pupils watch a demonstration andanswer questions.

Reacting metals with acids Pupils carry out an experiment to reactmetals with dilute hydrochloric acid.

Relatively reactive Pupils use a database to classify metals in orderof reactivity.

Electrons in atoms The most able pupils are encouraged to make thelink between the periodic table and the arrangement of electrons inatoms.

Approx. timing

20 min

10 min

15 min

15 min

15 min

Target group

C H E S

R/G G R S

✔

✔ ✔ (✔)

✔ ✔ ✔

✔

Key wordscorrosive, acid, salt, red only: base, alkali

Out-of-lesson learningHomework F2Textbook F2 end-of-spread questionsActivity F2d


• understand the basic metal/acid reaction• appreciate that more reactive metals produce the

same amount of hydrogen faster rather thanproducing more hydrogen (all else being equal)

• understand that some metals react with water, butthat this is a slower reaction than that with acid.


• recall the basic metal/acid reaction• recall that some metals react with water.


• appreciate the emergent pattern ofreactivity.



F3Lesson planning

guideChanging places


Recap last lesson

Whole group discussionfocusing on how thereactivity of metalsvaries.

Learning objectivesi A simple model for displacement reactions.ii How relative reactivity controls displacement.iii Atoms can gain or lose electrons during a reaction. (extension only)

Scientific enquiryiv Observe patterns in data. (Framework YTO Sc1 9f)v Use data to make interpretations and recognise the importance of negative results.

Learning outcomes

Share learning objectives

• Describe what happens inmetal displacement reactions.

• Use a simple model to explainhow reactivity affectsdisplacement reactions. (Sc1)

Problem solving

Pupils use their knowledgeof metal reactions tosuggest tests to identifyfive different metals.

Word game

Matching exercise to matchsubstances with theirdescriptions.

Capture interest

Demo of copper-plating ironobjects.


Review learning

Game to predict if a reactionwill happen between namedpairs of metals and metalcompounds.

Sharing responses

Pupils feed back theiroutcomes of Activity F3a anddiscuss why negative resultsare important in experiments.

Group feedback

Groups make shortpresentations to show theirideas about displacementfrom Activity F3b.

Word game

Anagram game.

Looking ahead

Pupils are asked to suggest onemetal that would displace allthe metals used today, and onethat would not.


Textbook F3


Activity F3b Practical

Activity F3c Paper


i and ii

i, ii, iv and v

i, ii, iv and v

iii

Description


Displacement reactions Pupils investigate displacement reactions ofthree metals.

Displacement in action Pupils carry out displacement reactions toplate metals.

Atoms and ions The most able pupils look at what happens in termsof electrons during displacement reactions.

Approx. timing

20 min

20 min

15 min

15 min

Target group

C H E S

R/G G R S

✔ ✔

✔

✔

Key wordsdisplace, displacement reaction

Out-of-lesson learningHomework F3Textbook F3 end-of-spread questionsActivity F3c


• understand qualitatively what happens in adisplacement model using the ‘reaction race’ analogy

• understand that a more reactive metal willdisplace a less reactive metal from its compound

• know that displacement reactions can release a lotof energy

• appreciate that the ‘reactions race’ idea can beused to stop iron rusting.


• appreciate that some metals can push othersout of their compound

• know that displacement reactions can releasea lot of energy

• be able to use patterns of reactivity toexplain displacement reactions.


• use the particle model to understand whatis happening in a displacement reaction

• appreciate what is shown by a balancedchemical equation

• recognise that negative results are usefulto prove a pattern.



F4Lesson planning

guideWho’s top of the league?

Learning objectivesi Know about the reactivity series.ii Know that a more reactive metal can displace a less reactive metal from its compounds.

Scientific enquiryiii Draw conclusions from data, interpreting patterns and using them to make predictions. (Framework YTO Sc1 9f)iv Present and interpret observations using charts. (Framework YTO Sc1 9e)


Textbook F4

Activity F4a Paper


i and ii

i, ii, iii andiv

Description


Using reactivity data Pupils use data from two experiments, oneinvolving temperature change, to rank metals in order of reactivity.

Advance warning Tell pupils which metal they will be researching inActivity F5a. Ask them to carry out web searches to find informationon its properties, uses and extraction.

Approx.timing

20 min

30 min

Target group

C H E S

R/G G R S

✔ (✔)

Learning outcomes


• use the data given to arrange the tenmetals into a correct reactivity series

• use this reactivity series to makepredictions.


• appreciate that metals can be arranged in orderaccording to their reactivity.

Some pupils, making more progress will ...

• appreciate the wider significance of thereactivity series and how it may be applied

• be able to suggest experiments to deduce thereactivity of different metals.

Key wordsreactivity series

Out-of-lesson learningHomework F4Textbook F4 end-of-spread questionsActivity F4a


Recap last lesson

Quick quiz aboutdisplacementreactions.


• State the reactivity series for somemetals.

• Predict what displacement reactions willwork using the reactivity series. (Sc1)

Problem solving

Pupils work out the relativereactivity of lead and zinc from a demonstration ofdisplacement.

Brainstorming

In groups, pupilsdiscuss how to findout the reactivities ofdifferent metals.

Capture interest

Making an ‘initial badge’ bydisplacement.


Review learning

The class produces a list ofkey facts about metalreactivity.

Sharing responses

Pupils compare theoutcomes of Activity F4a.

Group feedback

Group work to makereactivity series display.

Word game

Play ‘React or not?’ cardgame.

Looking ahead

Pupils discuss how tochoose the right metal forthe job.



F5Lesson planning

guideReactivity in action

Learning objectivesi How the reactivity series can be used.ii How reactivity and metal properties affect the way metals are used.

Scientific enquiryiii Apply recognised patterns to understand/predict metal usage. (Framework YTO Sc1 9f)iv Search for and choose secondary data to explain the uses of metals. (Framework YTO Sc1 8d)


Recap last lesson

In groups pupils writedefinitions of keywords.


• Explain why different metals arechosen for different jobs.

• Select relevant information aboutmetals using different sources. (Sc1)

• Select a suitable method ofpresentation to communicateinformation. (Sc1)

Problem solving (1)

How can copper bereclaimed from spoilheaps?


Show photos of the range,uses and extraction ofmetals.Catalyst InteractivePresentations 3


Demonstration of thermitreaction.Catalyst InteractivePresentations 3


Textbook F5

Activity F5a Discussion


i and ii

i, ii, iii andiv

Description


Uses of metals Pupils research the extraction and uses of metals andmake a presentation.

Approx.timing

20 min

30 min

Target group

C H E S

R/G G R S

✔ ✔ ✔


Review learning

Brainstorm of how metalsare used.

Sharing responses

Presentations of outcomesof Activity F5a.

Group feedback

Groups combine to discusshow they carried out theirresearch in Activity F5a.

Word game

Pupils match metals to theiruses.

Looking back

Pupils revise andconsolidate knowledge fromthe unit.

Learning outcomes


• understand how metal reactivity affectsthe uses to which metals may be put

• understand how the reactivity series canbe used to get metals from theircompounds

• be able to carry out focused research.


• appreciate why some metals are used forparticular purposes

• be able to find out facts about a metal.


• understand how metal discovery was closelylinked to the reactivity series

• research complex ideas and be selective aboutwhich information to use

• be able to use the reactivity series to makepredictions.

Key wordsNone

Out-of-lesson learningHomework F5Textbook F5 end-of-spread questionsRead fiction and poems, e.g. Charcoal Burners, about the search formetals



F6Lesson planning

guideVariables together – Think aboutvariables that interact

Learning objectivesi Know how iron rusts and that the two variables interact.ii Know that some conditions make iron rust faster.iii Know some techniques for rust prevention.The structure of this lesson is based around the CASE approach. The starter activities give concrete preparation. The main activities move away from theconcrete towards a challenging situation, where pupils need to think. The extended plenary gives pupils time to discuss what they have learnt, tonegotiate a method to commit to paper and express their ideas verbally to the rest of the class.

Scientific enquiryiv Consider strategies used when planning experiments. (Framework YTO Sc1 9b)v Draw conclusions from data and appreciate the limitations of the data. (red only) (Framework YTO Sc1 9g)


Bridging to the unit

Display of corroded objects to link toprevious lessons.

Setting the context

Show car adverts and discuss why it is important tounderstand rusting.

Concrete preparation

Using a bike as an example, pupils make a list offactors that may affect whether or not iron rusts.


Textbook F6

Activity F6aPractical


i, ii and v

i, ii, iii, ivand v

Description


Variables in rusting Pupils analyse the results of an experiment setup to investigate rusting.

Approx.timing

30 min

20 min

Target group

C H E S

R/G G R S

✔


Group feedback

Groups feed back to the whole group on the outcomes of theirinvestigations.

Bridging to other topics

Focus on variables that interact in rusting and in other examples inscience.

Learning outcomes


• interpret the data so that they understandhow it shows that both oxygen and waterare needed to make iron rust

• be able to suggest some strategies forinvestigating rust prevention.


• know that both oxygen and water are needed tomake iron rust

• know that using a barrier to oxygen and waterstops iron rusting.


• appreciate the limitations of given data andsuggest ways to improve the investigation

• be able to develop a complex strategy forinvestigating multiple variables that affect therusting of iron

• be able to interpret their results to evaluaterust prevention techniques and identify factorsthat increase rate of rusting.

Key wordsvariable, interact, red only: independent, dependent

Out-of-lesson learningTextbook F6 end-of-spread questions


F Unit mapPatterns of reactivity


Copy the unit map and use these words to help you complete it.You may add words of your own too.

coppercorrosiondisplacementenergyextractiongoldhydrogenironless reactivemetal hydroxide

metal oxidemore reactiveoreoxygenpotassiumrustingsaltstemperaturethermit reaction

Patterns ofreactivity

Metals reactingwith air

Preventing rusting

Reactivity series anduses of metals

Metals displacing metals

Metals reactingwith water and

acids

Unitmaps.qxd 18-Jun-04 11:36 AM Page 6


F1 StartersLosing that shine

Introduce the unit� Either draw the outline of the unit map on the board then ask pupils

to give you words to add, saying where to add them. Suggest somewords yourself when necessary to keep pupils on the right track.

� Or give out the unit map and ask pupils to work in groups decidinghow to add the listed words to the diagram. Then go through it onthe board as each group gives suggestions.

Share learning objectives� Write learning objectives on the board and illustrate why it is

important that we know about these ideas.� Tell pupils that iron is used in far greater amounts than any other

metal, e.g. in cars, electrical appliances, bridges, machinery infactories, buildings etc. However, it has to be replaced because it rustsaway so that the products or machinery are unsafe or stop working.

� Understanding why metals corrode has helped scientists andengineers develop methods of preventing corrosion, e.g. most carshave a 5 year anti-corrosion warranty because the iron undercarriageis now sealed in plastic, oil protects the engine and the bodywork issealed in zinc and paint to stop corrosion.

Brainstorming� Show pupils the photograph of the iron bridge. A local alternative

could be used.� Write the suggested questions on the board. Ask pupils to work in

groups to brainstorm their ideas and then feed back to the class.� Focus discussion on the idea that iron reacts to form rust and that

this can be prevented by coating the iron in an airtight coating (mostmodern bridges are alloyed).

Capture interest (1)� Show pupils a display of ‘gold’ cheap jewellery and compare prices to

real gold in a catalogue.� Discuss the cost of real versus fake and what will happen to the cheap ‘gold’.� Discuss the idea that ‘cheap’ jewellery often contains cheaper metals

like iron that react with substances in the air (and people, whichcauses allergic reactions). Gold does not react.

Capture interest (2)� Show pupils photos of metal objects of different ages.

� Ask them why they think metal objects corrode at different rates.

� Focus on the idea that different metals corrode at different rates, andthe conditions they are under can affect the rate of change.

➔ Unit map

➔ Catalyst InteractivePresentations 3

Questions1 Why is iron a good material

for building bridges?2 What changes happen as

the bridge gets older? Whydo they happen?

3 How long will the bridge last?4 What can be done to make

a bridge last longer?

Equipmentcheap ‘gold’ jewellery (it doesnot matter if it is alreadytarnished); pictures of realgold jewellery in a catalogueshowing prices



Introduce the unit

Unit map for Patterns ofreactivity.


• Describe what happens whenmetals corrode.

• Explain patterns in the waymetal objects corrode. (Sc1)

Brainstorming

Pupils consider the lifeof an iron bridge.Catalyst InteractivePresentations 3


Show pupils fake goldjewellery and discusswhether it will corrode.


Show photos of differentmetals and discuss howthey change over time.Catalyst InteractivePresentations 3

F-Starters.qxd 08-Jun-04 12:25 PM Page 1


F2 StartersCorrosive liquids

Recap last lesson� Write the questions on the board.

� Pupils work in pairs to answer the questions.

� Pairs combine into a group of four to compare answers.

� A spokesperson feeds back any areas of uncertainty to wholeclass as a short plenary.

Share learning objectives� Ask pupils to write a list of FAQs they would put on a

website telling people about acids. Collect suggestions as awhole-class activity, steering pupils towards those related tothe objectives. Conclude by highlighting the questions youwant them to be able to answer at the end of the lesson.

Problem solving� Remind pupils of the differences between physical (e.g. no

new substances made, can be easily reversed, for example,state changes) and chemical (e.g. new substances made, noteasily reversed) changes.

� Pupils look at the contexts described on the pupil sheet.They decide which is a chemical and which is a physicalchange and give evidence for their ideas.

� They should realise that the re-shaping of iron is a physicalchange, but rusting is a chemical change.

Brainstorming� Tell pupils that two treasure chests of ancient gold and metal

coins have been found – one on land, one in the sea. Askthem what they expect to see when they open the chests.

� Make a list of their ideas on the board. Focus discussion onthe idea that most metals corrode much faster in water (after100 years, very few metal objects are left on the Titanic, forexample) than in air, but very unreactive metals, such asgold, do not corrode at all.

Capture interest� Pupils watch video clips of very reactive metals reacting

with water. Compare this to the much slower processes ofmore common metals corroding in wet conditions.

Questions1 Why does gold stay shiny but iron

goes rusty very quickly?2 Why are sodium and potassium

stored in dark jars full of oil?3 What is used up in the air when

shiny zinc goes dull?4 Magnesium is used to make blue

flashes in fireworks. It reacts withoxygen. What does magnesiummake when it reacts with oxygen?

Answers1 Gold is unreactive; iron is much morereactive; 2 The jars keep light, waterand oxygen away from the very reactivemetals; 3 oxygen; 4 Magnesium oxide.

➔ Pupil sheet

➔ Catalyst Interactive Presentations 3


Recap last lesson

Quick quiz in groups aboutmetals reacting with air.


• Describe what happens whenmetals react with water andacids.

• Predict how reactive a metalis from experimentalobservations. (Sc1)

Problem solving

Chemical changes in ablacksmith’s.

Brainstorming

Corrosion of coins intreasure chests.

Capture interest

Show a video clip ofreaction of group I metals,including rubidium andcaesium, with water.Catalyst InteractivePresentations 3


XX Starters


F2 Corrosive liquids

Problem solving

Joe is a blacksmith. He makes iron shoes for horses.

Joe heats iron until it is so hot that it can easily be bent to fit the horse's foot.When it cools down it looks grey and shiny.

Joe has some old shoes in his shop. They used to be grey and shiny but are nowcovered in lumps of red rust.

Questions

1 Which change in Joe’s shop is a physical change? Which is a chemical change?

2 Use ideas from the diagrams to explain how you can tell.



F3 StartersChanging places

Recap last lesson� Ask pupils to suggest ways that different metals behave

differently.

� Use pupil responses to make a list on the board.

� Encourage pupils to think in terms of the differences inreactions of more reactive and less reactive metals.

� Focus on the difference in reactivity of metals withoxygen, water and acids.

Share learning objectives� Write learning objectives on board and illustrate why it

is important that we know about these ideas.

� Tell pupils that when metals are taken from the groundthey are usually in the form of compounds in rocks.Engineers and scientists use data about the reactivity ofthe metals to decide how to extract the useful metal andwhat metals are suitable to use for different purposes.

Word game� Pupils link each substance to the correct description on

the pupil sheet.

Problem solving� Tell pupils to think about five grey metals: sodium,

silver, calcium, magnesium and iron.

� Ask them to work in small groups to make a list of teststhey could do, with the results they would expect, toprove which is which.

Capture interest� Put an iron object, such as a key, into a petri dish

containing dilute copper sulphate (it is best to use ‘one I made earlier’ as this takes a few minutes to work).

� Show pupils that the key has become plated withcopper.

� Tell them that this has happened because iron andcopper have different reactivities.

➔ Pupil sheet

Answerscopper: 4; hydrogen: 3; iron: 2; oxygen: 1;sodium: 5; sulphuric acid: 6

AnswersSuggestions should include testing withwater or acid, or leaving for a week or so in air.

Equipmentpetri dish containing dilute (approx 1 mol/dm3 will work) copper sulphate; iron object such as a key


Recap last lesson

Whole group discussionfocusing on how thereactivity of metals varies.


• Describe what happens inmetal displacementreactions

• Use a simple model toexplain how reactivityaffects displacementreactions. (Sc1)

Problem solving

Pupils use theirknowledge of metalreactions to suggesttests to identify fivedifferent metals.

Word game

Matching exercise to matchsubstances with theirdescriptions.

Capture interest

Demonstration of copper-plating iron objects


F3 StartersChanging places

Sheet 1 of 1

Sheet 1 of 1

© Harcourt Education Ltd 2004 Catalyst 3This worksheet may have been altered from the original on the CD-ROM.

StartersF3 Changing places

Word game

Match these words to the correct descriptions.


Word game

Match these words to the correct descriptions.

1 2 3I react with metals to make I react slowly with acids. I am a gas that fizzesthem look dull. when metals react with

acids.

4 5 6I am a lazy metal that does I am a metal but don’t I make metal sulphates not react with acids. touch me! I am so reactive when I react with metals.

I will burn your fingers!

copper oxygen sodium sulphuric acidironhydrogen

1 2 3I react with metals to make I react slowly with acids. I am a gas that fizzesthem look dull. when metals react with

acids.

4 5 6I am a lazy metal that does I am a metal but don’t I make metal sulphates not react with acids. touch me! I am so reactive when I react with metals.

I will burn your fingers!

copper oxygen sodium sulphuric acidironhydrogen



F4 StartersWho’s top of the league?

Recap last lesson� Pupils write down their answers to verbal questions.

� Ask pupils to mark each other’s answers. Groups feedback by a spokesperson raising a hand to identify whichquestions more than one person in their group answeredwrongly.

Share learning objectives� Ask pupils to write a list of FAQs they would put on a

website telling people about displacement. Collectsuggestions as a whole-class activity, steering pupilstowards those related to the objectives. Conclude byhighlighting the questions you want them to be able toanswer at the end of the lesson.

Problem solving� Demonstrate the displacement of lead by dipping a

cleaned zinc strip in a solution of lead nitrate in a boilingtube.

� Ask pupils to work in groups to decide which is the mostreactive metal, lead or zinc.

� Ask pupils to suggest some other experiments to provethis.

Brainstorming� Allow pupils time in their groups to think of some ideas

to answer the question. Ask a spokesperson from eachgroup to feed back ideas and make a whole classsummary on the board.

� Look for several methods, e.g. rates of tarnishing,reaction with oxygen, water, acids and displacementreactions, measuring energy changes during reactions.

� For less able pupils, it may be simpler to give actualexamples of metals for them to think about, e.g. ‘Howcan you tell that sodium is more reactive than iron?’.

Capture interest� Show pupils how an ‘initial badge’ can be made by

displacement.


Recap last lesson

Quick quiz aboutdisplacement reactions.


• State the reactivity series forsome metals.

• Predict what displacementreactions will work using thereactivity series. (Sc1)

Problem solving

Pupils work out therelative reactivity of leadand zinc from ademonstration ofdisplacement.

Brainstorming

In groups, pupils discusshow to find out thereactivities of differentmetals.

Capture interest

Making an ‘initial badge’ bydisplacement.

Questions1 What is the word for when zinc pushes

copper out of copper sulphate solution?2 What metal is made when zinc reacts

with copper sulphate solution?3 We use this piece of equipment to show

that energy is given out when zincreacts with copper sulphate solution.

4 Name one metal that will not reactwith copper sulphate solution.

5 Magnesium is very reactive. Doesmagnesium react with copper sulphate?

Answers1 displacement; 2 copper; 3 thermometer/temperature probe; 4 gold/silver/copper; 5 yes

➔ Teacher and technician sheet

Question1 How can you find out the reactivities of

different metals?

➔ Teacher and technician sheet



Problem solvingTeacher and technician sheet

Equipment

� lead nitrate (0.4 mol/dm3)

� zinc strip cleaned as described in Activity F3b

� boiling tube and rack

� (optional) digital microscope and light projector

1 Show pupils the displacement of lead by zinc (it is best to set this up inadvance to get larger crystals forming). A digital microscope can be usedto show the crystals of lead forming on the zinc strip.

2 Write the equation for the reaction on the board (more able pupils can beasked to deduce the right hand side).zinc + lead nitrate → lead + zinc nitrate

3 Ask them to consider the answers to these questions in their groups.Which is more reactive, lead or zinc? [zinc]

What other experiments could you do to prove it?[add lead to zinc nitrate – no reaction; add both metals to dilute acid, zinc reacts faster; watch tarnishing reaction in air, zinc reacts faster]


zinc strip

boiling tube

lead nitrate

Wear eyeprotection.

Leadnitrate istoxic,

avoid contact withskin.



Capture interestTeacher and technician sheet

Equipment

� copper sulphate (1 mol/dm3)

� zinc strip cleaned as described in Activity F3b

� boiling tube and rack

� clear nail varnish

1 Write an initial on the zinc strip using clear nail varnish.

2 Ask pupils to predict what will happen when the strip is left in coppersulphate solution.

3 Carry out the demonstration – after a few minutes the zinc will be copperplated, but the protected area will stay silver coloured.


zinc strip

copper sulphatesolution

boiling tube

zinc strip

initial

clearnail varnish



F5 StartersReactivity in action

Recap last lesson� Write the key words that the pupils have met so far in the topic on the board.

� Pupils work in small groups to write down what they think each term means.

� Ask a spokesperson to feed back and summarise an acceptable explanation foreach term on the board.

� Pupils copy the whole-class summaries to keep for revision.

Share learning objectives� Write learning objectives on board.

� Ask pupils to brainstorm what metal objects they have used so far in theirday.

� Highlight that for each purpose the ‘right’ metal needs to be chosen or thesevarious objects would not work or would have too short a lifespan. Thisillustrates that it is important to know how metals react.

Problem solving� Pupils look at the description of reclaiming copper from waste spoil heaps on

the pupil sheet (this can be shown as an OHT) and work through the task.

� Possible ideas include, concentrating by evaporation (cheap in hot countries,no fuel needed), add iron (cheap metal more reactive than copper). More ablepupils may take this further by suggesting filtration to remove the copperformed. Excess iron in the copper can be removed by reacting it with diluteacid. (This process is already in use – it involves bacterial leaching.)

Capture interest (1)� Show pupils the photographs. Highlight the huge scale of the uses of metals

and how important they are to our lives, work and wealth.

� Explain that most examples use alloys that are mixtures of metals: this altersthe properties of the material.

� Focus on the huge range of uses for metals in industry and the importance ofchoosing the right metal for each use to ensure that the products functionproperly and have an appropriate lifespan.

Capture interest (2)� Demonstration of the thermit reaction to illustrate the ideas covered in the

book.

� Show pupils photo of the thermit reaction being used.

Key wordsdisplacement, metalreactivity, corrosive,corrosion, salt

➔ Pupil sheet


➔ Teacher andtechnician sheet



Recap last lesson

In groups pupils writedefinitions of key words.


• Explain why different metalsare chosen for different jobs.

• Select relevant informationabout metals using differentsources. (Sc1)

• Select a suitable method ofpresentation to communicateinformation. (Sc1)

Problem solving

How can copper bereclaimed from spoilheaps?


Show photos of the range,uses and extraction ofmetals.Catalyst InteractivePresentations 3


Demonstration of thermitreaction.Catalyst InteractivePresentations 3




Problem solving

Copper is very expensive. Supplies of copper in the ground arerunning out. Scientists are working to devise a way of reclaimingcopper from waste heaps.

This diagram shows the first stage of the process. The processneeds to work on a very big scale so needs to be cheap.

Your task is to work out how copper can be made from the verydilute copper sulphate solution.

Work as a group to think about the problem.

You need to consider...

� The solution is very dilute and needs to be made moreconcentrated. How can you do this cheaply?

� What can you add to copper sulphate that will react to formcopper? (Hint – think displacement!) Think about cost in youranswer.

� How could you get clean copper solids after the reaction hasfinished?

� Choose a spokesperson to feed back your ideas to the wholeclass.

spray withdilute sulphuric

acid

waste heapcontaining tiny

amounts ofcopper compounds

water running offcontains very dilute

copper sulphatesolution



Capture interest (2)Teacher and technician sheet

Equipment

� iron oxide � dry sand

� aluminium powder � barium peroxide and magnesium powder ‘starter’

� large crucible or small plant pot � long fuse of magnesium ribbon

� bucket � Bunsen burner and spill or small gas blow lamp

Note: the iron oxide and aluminium powder must be very well mixed. The fuse needs to be long enough togive the teacher the opportunity to stand well back.

1 Set up the apparatus behind tall safety screens. It is wise to practise carrying out the reactionbeforehand.

2 Alternatively, the reaction can be carried out outside with all the pupils standing well back (3–4 metres)and wearing eye protection.

3 To initiate the reaction make a hole in the thermit mixture, gently pour in the ‘starter’ and insert themagnesium ribbon fuse.

4 Light the magnesium fuse using a spill. Alternatively, the magnesium fuse can be lit using a hand-heldBunsen burner (great care!) or a butane blowlamp.

5 Stand well back! The reaction is very spectacular with lots of flames and sparks.

6 Show pupils the photograph of the reaction in use on the railways.

7 Draw attention to the word equation. The iron produced is molten at the very high temperature of thereaction and seals the two rails together

Equation

iron oxide + aluminium → aluminium oxide + iron

8 Highlight the importance of this reaction to the development of the railways.

Safety noteAll present need eye protection. If done outside a calm windless day is essential. Staff who have not donethis before require practice in the procedure under the supervision of an experienced member of thescience department. The procedure must be very closely followed. Tried and tested variations appear in anumber of ASE and CLEAPSS publications. No others should be used.


iron oxide andaluminium powder

clay pot

bucket

sand

magnesiumribbon

Wear eyeprotection.

Carry out thereactionbehind tallsafety screens.



F6 StartersVariables together – Think about

Bridging to the unit� Show pupils a display of heavily corroded objects.

� Ask them questions to check their understanding ofcorrosion.

� Write the word equation for rusting on the board.

Setting the context� Show car adverts either from magazines or as recorded

clips from TV. Stress that car manufacturing is a hugebusiness and that rusting causes car bodywork to be lesssafe and engines to break down. Stress that no othermetal can replace iron due to costs.

� Understanding the rusting process has enabled bettercorrosion prevention techniques to be used. Carmanufacturers now give 5 year anti-corrosionwarranties.

� Ask pupils to suggest ways that cars are protected fromrusting (e.g. painting, oiling, sealing undercarriages, useof plastics and alloys for smaller components).

Concrete preparation� Either look at a bike and ask pupils to think about why

bike parts go rusty and to list how iron is preventedfrom rusting.

� Or ask pupils to think about cars and bikes and make alist of ways that iron is prevented from rusting.

� Focus on conditions of rusting, e.g. wet bikes, and howbike parts are protected, e.g. plastic coatings, greasedchains, alloys, paint/varnish.

� List pupils’ ideas on the board and use them to decidewhat factors affect iron rusting.

Equipmentheavily corroded objects, e.g. old nails,bolts, etc.

Questions1 What is needed for iron to go rusty?

2 What does the iron react with?

3 What is the chemical name for rust?

4 What conditions make iron rust faster?

Answers1 oxygen and water; 2 oxygen; 3 iron oxide; 4 acidic, salt, etc.


Bridging to the unit

Display of corroded objects to link to previouslessons.

Setting the context

Show car adverts and discuss why it isimportant to understand rusting.

Concrete preparation

Using a bike as an example, pupils make a list offactors that may affect whether or not iron rusts.


F1aTeacher

activity notesReactive metals and oxygen

Running the activityShow pupils jars containing sodium and either lithium or potassium stored under oil. Pointout that these metals are so reactive that they are stored in dark bottles under oil to excludeair and light.

Demonstrate the reaction of each metal with air as follows.

1 Remove a piece of the metal from the oil using forceps and place on a ceramic tile. Theoil can be removed, if necessary, using a tissue.

2 Cut the metal using a scalpel to reveal a shiny surface.

3 Ask pupils to watch as the surface quickly becomes dull as the metal tarnishes. This canbe seen more clearly using a digital microscope linked to a light projector, if available.

4 Discuss the reaction between the metal and oxygen and write a word equation on theboard to show a metal oxide is formed.

Tell pupils that many (but not all) other metals react with oxygen but the reactions aremuch slower. More able pupils may notice that the rate of tarnishing varies between themetals they see.

Show pupils samples of shiny and heavily corroded iron. Draw attention to the fact that thereaction is similar, but too slow to be seen happening.

For your information:

lithium + oxygen → lithium oxide4Li + O2 → 2Li2Osodium + oxygen → sodium oxide4Na + O2 → 2Na2Opotassium + oxygen → potassium oxide4K + O2 → 2K2Oiron + oxygen → iron oxide2Fe + 3O2 → 2FeO3

Expected outcomesAll metals tarnish very quickly in air. Potassium reacts fastest, then sodium and lithiumslowest of all (there is no need to show pupils all three). This is related to the relativereactivity of the metals, which increases down group I of the periodic table.

Safety notesEye protection should be worn.

The reactive metals should be stored in a secure place out of the reach of the pupils untilneeded, and returned to safe storage immediately after the demonstration.

ICT opportunitiesUse of a digital microscope and light projector.

Pupils search the Internet for reactions of metals with oxygen.Relevant sites include:WebElements Periodic TableRSC’s chemical science network: visual interpretation of the Table of Elements


Type Purpose DifferentiationPractical Demonstration to show pupils that metals react at different rates with oxygen in the air

to form metal oxides.CoreNo pupil sheets

F-Teachers.qxd 09-Jun-04 4:19 PM Page 1

http://www.heinemann.co.uk/hotlinks/url.asp?urlid=9590


F1aTechnician

activity notesReactive metals and oxygen

Equipment neededFor the teacher:

� small piece of sodium and either lithium or � white tile, scalpel, forcepspotassium stored under oil

� samples of heavily corroded iron e.g. nails and bolts � (optional) digital microscope and light projector

For your informationRunning the activityShow pupils jars containing sodium and either lithium or potassium stored under oil. Point out that thesemetals are so reactive that they are stored in dark bottles under oil to exclude air and light.

Demonstrate the reaction of each metal with air as follows.

1 Remove a piece of the metal from the oil using forceps and place on a ceramic tile. The oil can beremoved, if necessary, using a tissue.

2 Cut the metal using a scalpel to reveal a shiny surface.

3 Ask pupils to watch as the surface quickly becomes dull as the metal tarnishes. This can be seen moreclearly using a digital microscope linked to a light projector, if available.

4 Discuss the reaction between the metal and oxygen and write a word equation on the board to show ametal oxide is formed.

Tell pupils that many (but not all) other metals react with oxygen but the reactions are much slower. Moreable pupils may notice that the rate of tarnishing varies between the metals they see.

Show pupils samples of shiny and heavily corroded iron. Draw attention to the fact that the reaction issimilar, but too slow to be seen happening.

For your information:

lithium + oxygen → lithium oxide4Li + O2 → 2Li2Osodium + oxygen → sodium oxide4Na + O2 → 2Na2Opotassium + oxygen → potassium oxide4K + O2 → 2K2Oiron + oxygen → iron oxide2Fe + 3O2 → 2FeO3

Expected outcomesAll metals tarnish very quickly in air. Potassium reacts fastest, then sodium and lithium slowest of all (thereis no need to show pupils all three). This is related to the relative reactivity of the metals, which increasesdown group I of the periodic table.

Safety notesEye protection should be worn.The reactive metals should be stored in a secure place out of the reach of the pupils until needed, andreturned to safe storage immediately after the demonstration.

ICT opportunitiesUse of a digital microscope and light projector. Pupils search the Internet for reactions of metals with oxygen.Relevant sites include:WebElements Periodic TableRSC’s chemical science network: visual interpretation of the Table of Elements


Type Purpose DifferentiationPractical Demonstration to show pupils that metals react at different rates with oxygen

in the air to form metal oxides.Core No pupil sheets

F-Technician.qxd 08-Jun-04 2:32 PM Page 1



F1bTeacher

activity notesTarnished metal

Running the activityPupils work independently or in small groups to answer the questions on theworksheets. Less able pupils may need support to help them think about whatconditions apply to each diagram, e.g. ‘wet’ ‘dry’ ‘no air’ etc.

ICT opportunitiesPupils could search the Internet for ‘Stainless steel composition’. Stainless steelis made from chromium added to iron. The chromium stops the iron fromrusting so that it can be used for surgical instruments, ‘hypoallergenic’jewellery and cutlery. Alloying is more efficient than plating because theplating is prone to flaking off.

Answers1 1 Dry, plenty of air, hot. 2 Cold, no air, wet. 3 Warm, wet, plenty of air.

4 Warm, wet, plenty of air. 5 Cold, wet, plenty of air.

2 Box 5 shows that chromium does not corrode when it is wet. Box 3 showsthat iron corrodes quickly when it is wet. (Note that both pieces ofinformation are needed.)

3 Iron does not rust in diagram 1 because there is no water. In diagram 2there is no air. Iron rusts quickly in diagram 3 because there is air and water(and it is warm).


Type Purpose DifferentiationPaper Pupils answer questions about gold, iron and chromium corroding under different

conditions.Core


F1bActivity

CoreTarnished metal

Metals tarnish when they react with oxygen in the air.

These diagrams show how different metals tarnish (go dull)and corrode under different conditions.


1 Archaeologists have found gold and ironobjects buried in the dry sands of theEgyptian desert. They look new eventhough they are thousands of years old.

2 A Viking knife made of iron was foundburied under wet, airtight clay. It wasonly a little rusty after being buried forover a thousand years.

3 Iron door hinges in a warm, wetbathroom go very rusty after only a few weeks.

4 Gold rings stay shiny for years, eventhough people wear them all the time.

5 Old car bumpers used to be plated withchromium. This metal stays shiny evenwhen it keeps getting wet.

1 Describe the conditions in each diagram, for example, ‘verywet with lots of air’.

2 What information shows that iron is more reactive thanchromium?

3 Explain why the iron objects have corroded at different rates.

F-Activities.qxd 08-Jun-04 12:36 PM Page 1

F1cTeacher

activity notesInside the atom

Running the activityA pupil capable of dealing with the concept of atomic structure should be capable ofworking through this sheet alone. However, with a very able class, the teacher may wishto talk about atomic structure and then give pupils the sheet to complete in class or forhomework.

Expected outcomesCompleted questions showing understanding of the concept.

PitfallsAtomic structure is a KS4 topic and should only be broached with pupils who arecomfortable with using scientific models and with formal scientific thinking. Each schoolshould consider whether they wish to broach this KS4 concept during the KS3 course.

Answers1 11 protons

2 11 electrons

3 a 2 electrons

b 8 electrons

c 1 electron

4 (Possible answer) In a cell.

They are both in the middle.

5 –11 + +11 = 0

6 a 6 protons

b 6 electrons

c


Type Purpose DifferentiationPaper To stretch the most able pupils, by dealing with the concept of atomic structure. Extension


F1cActivity

ExtensionInside the atom

You are going to learn about a model that scientists use todescribe what is inside the atom.

Atoms have a central part called the nucleus. The nucleus contains the protons. Whizzing around the nucleus are the electrons.

The electrons are grouped together. The group closest to the nucleus is said to make up the ‘inner shell’, and the second closest group makes up the ‘second shell’. An atom can have up to seven ‘shells’.

The sodium atom in the diagram has three shells,represented by the three circles around the central nucleus.

1 How many protons are in the sodium atom?2 How many electrons are in the sodium atom?3 How many electrons are in:

a the inner shellb the next shellc the outer shell?

4 Where else have you heard the word ‘nucleus’? What is similar about the atom’s nucleus and the other nucleus?

The shells are filled up in order from the inside. The inner shell can take two electrons and the second shell takes eight electrons. Sodium has one more electron, which is in the outer shell.

You may remember electrons from when you studied electricity. Electrons move along the wires, carrying the energy. If you made a wire out of sodium (difficult and dangerous, but not impossible) it would be the electron from the outer shell that moved between atoms, carrying the energy.

Protons and electrons are charged and charge comes in both negative and positiveamounts. Electrons have a charge of –1 each. Protons have a charge of +1 each.

5 Add up all the charges in the sodium atom.

Atoms in an element contain the same number of protons as electrons. This means thatthe overall charge of an atom in an element is zero.

The number of protons in an atom is called the atomic number. For the atoms in an element, the atomic number also gives the number of electrons, because the number of protons equals the number of electrons.

6 Carbon has atomic number 6.a How many protons does it have?b How many electrons does it have?c Look at the diagram for the sodium atom. Draw a similar

diagram for a carbon atom.


proton

electron


F2aTeacher

activity notesReacting metals with water

Running the activityBefore carrying out the demonstration, ask pupils to copy the results table so that they can complete itduring the demonstration. The table could be enlarged and photocopied for less able pupils.

Demonstrate the reaction of sodium with water as shown in the diagram. The sodium can be cut usingforceps and a scalpel, on a ceramic tile. The piece should be wiped with a tissue to remove any oil. Addenough universal indicator solution to give a distinct green colour to the water before starting.

Draw pupils’ attention to the observations that the sodium floats and fizzes (implying a gas is made) andthat the universal indicator goes blue due to the formation of an alkali (sodium hydroxide). Write a wordequation on the board.

Sodium + water → sodium hydroxide + hydrogen

Repeat the demonstration using potassium and then calcium (it is easiest to use three separate troughs).Carry out the calcium experiment again, this time using a rice-grain sized piece in a test tube. Let the gasbuild up using a bung, and show pupils that the gas pops when a lighted splint is brought near, provingthat the gas is hydrogen. This can be used as a demonstration to remind pupils how to test for hydrogen inpreparation for Activity F2b.

Ask a pupil to feel the test tube after the reaction has finished – it feels warm due to energy being given outduring the reaction.

If not already shown as a starter, Catalyst Interactive Presentations 3 shows the reaction of more reactivemetals, rubidium and caesium, with water. These reactions can be shown and pupils make furtherobservations to add to their tables.


Type Purpose DifferentiationPractical Demonstration to show pupils that very reactive metals react very quickly with water to

produce a metal hydroxide and hydrogen.Core

forceps

small piece of metal

water and universalindicator

water

bung

calcium

lighted spill


F2aTeacher

activity notesReacting metals with water (continued)

Other relevant materialSkill sheet 15: Word equations

Expected outcomesPotassium reacts most vigorously, producing a flame of burning hydrogen. Theuniversal indicator goes blue as the hydroxide is formed. Sodium reactssimilarly, but not as vigorously, calcium slowest of all.

Safety notesAlways use a large trough of cold water. Never try to contain the sodium orpotassium on the surface of the water – let it run free. All present should weareye protection, and use a safety screen. Do not allow reactive metals to comeinto contact with skin.

ICT opportunitiesPupils can see the reactions by going to the following website: RSC’s chemical science network: visual interpretation of the Table of Elements

Answers1 a Potassium (or caesium if video is shown).

b (Caesium, rubidium), potassium, sodium, calcium.

2 1 Reaction is faster than with sodium.

2 Universal indicator goes blue.

3 Fizzing seen, lighted spill goes pop.

4 Flames seen for potassium, calcium makes the test-tube warm.

5 Sodium floats.

3 sodium + water → sodium hydroxide + hydrogencalcium + water → calcium hydroxide + hydrogenpotassium + water → potassium hydroxide + hydrogen




F2aTechnician

activity notesReacting metals with water

EquipmentFor demonstration:

� troughs of water (3 if possible) � universal indicator solution� sodium, potassium and calcium pieces � Bunsen burner and spills� forceps, scalpel, white tile, tissues � test tube, rack and bung


For your information

Running the activityBefore carrying out the demonstration, ask pupils to copy the results table so that they can complete itduring the demonstration. The table could be enlarged and photocopied for less able pupils.

Demonstrate the reaction of sodium with water asshown in the diagram. The sodium can be cutusing forceps and a scalpel, on a ceramic tile. Thepiece should be wiped with a tissue to remove anyoil. Add enough universal indicator solution to givea distinct green colour to the water before starting.

Draw pupils’ attention to the observations that thesodium floats and fizzes (implying a gas is made)and that the universal indicator goes blue due tothe formation of an alkali (sodium hydroxide).Write a word equation on the board.

sodium + water → sodium hydroxide + hydrogen

Repeat the demonstration using potassium and then calcium (it is easiest touse three separate troughs). Carry out the calcium experiment again, thistime using a rice-grain sized piece in a test tube. Let the gas build up usinga bung, and show pupils that the gas pops when a lighted splint is broughtnear, proving that the gas is hydrogen. This can be used as a demonstrationto remind pupils how to test for hydrogen in preparation for Activity F2b.

Ask a pupil to feel the test tube after the reaction has finished – it feelswarm due to energy being given out during the reaction.

If not already shown as a starter, Catalyst Interactive Presentations 3 showsthe reaction of more reactive metals, rubidium and caesium, with water.These reactions can be shown and pupils make further observations.

Expected outcomesPotassium reacts most vigorously, producing a flame of burning hydrogen. The universal indicator goesblue as the hydroxide is formed. Sodium reacts similarly, but not as vigorously, calcium slowest of all.

Safety notesAlways use a large trough of cold water. Never try to contain the sodium or potassium on the surface of thewater – let it run free. All present should wear eye protection, and use a safety screen. Do not allow reactivemetals to come into contact with skin.

ICT opportunitiesPupils can see the reactions by going to the following website: RSC’s chemical science network: visualinterpretation of the Table of Elements


Type Purpose DifferentiationPractical Demonstration to show pupils that very reactive metals react very quickly with water to

produce a metal hydroxide and hydrogenCore

forceps



water

bung

calcium

lighted spill




Many metals react with water. Some, like iron, react too slowly to see any change happen. Others react so quickly that the change can be seen in a few seconds. You are going to watch your teacher demonstrate how some reactive metals react withwater. You need to write down what you see happening.

Obtaining evidence

1 Make a larger copy of this table.

2 Write down your observations as your teacher carries out the demonstration.

Considering the evidence

1 a Decide which metal is most reactive.b Make a list of the metals in order, ‘most reactive’ to ‘least reactive’.

2 Eve watched the demonstration and wrote down these conclusionsin her exercise book:

1. Potassium is a more reactive metal than sodium.2. An alkali is made when the metals react with water.3. When metals react with water, hydrogen gas is made.4. Energy is given out during the reactions.5. Sodium is less dense than water.

What evidence did you see to support each of Eve’s statements?

3 The general equation for the reaction is

metal + water → metal hydroxide + hydrogen

Write word equations to show what happens for each reaction you saw.

F2aActivity

CoreReacting metals with water


forceps



Metal Observations

sodium

potassium

calcium

Wear eyeprotection.

Watch thereactionsthrough the

safety screen.


F2bTeacher

activity notesReacting metals with acids

Running the activityShow pupils the technique of testing for hydrogen. This can be done by emphasising the technique duringthe demonstration of the reaction between calcium and water in Activity F2a.

Ask pupils to design their tables for recording observations before starting the practical.

Emphasise the outcome that copper does not react with dilute acids.

Core: Follow instructions on Activity sheet F2b.

Help: This has a table to record observations and simplified questions.

Extension: Additional questions are available at the bottom of the core sheet.

Other relevant materialSkill sheet 33: More word equations

Expected outcomesCore: Magnesium reacts quickly with dilute acid and produces enough hydrogen to give a definite ‘pop’.Zinc fizzes less vigorously, iron produces bubbles slowly.

Help: As core, with less emphasis on Sc1.

Extension: Pupils have the opportunity of practising planning and predicting skills for Sc1.

PitfallsThe QCA Scheme of Work recommends that the acids used are at concentrations of 0.4 mol/dm3. This islower than was traditionally used for these experiments.

The reactions of iron and zinc are slow at this concentration. The hydrogen ‘pop’ test is unlikely to worksatisfactorily because only small quantities of hydrogen are evolved. Pupils need to look carefully tocompare the rate of bubbles of hydrogen evolved.

Safety notesWear eye protection. Wash any acid splashes off skin immediately.

AnswersCore:

1 Magnesium, zinc, iron, copper.2 Potassium, sodium, calcium, magnesium, zinc, iron, copper, gold. 3 zinc + hydrochloric acid → zinc chloride + hydrogen

iron + hydrochloric acid → iron chloride + hydrogen

Help:

1 Sodium, magnesium, zinc, iron, copper, gold.2 zinc + hydrochloric acid → zinc chloride + hydrogen

iron + hydrochloric acid → iron chloride + hydrogen

Extension:

4 zinc + sulphuric acid → zinc sulphate + hydrogeniron + sulphuric acid → iron sulphate + hydrogen

5 a magnesiumb Same volume of dilute acid; weighed samples of all four metals; measure temperature change during

reactions; magnesium should be greatest.


Type Purpose DifferentiationPractical Pupils carry out an experiment to react metals with dilute hydrochloric acid. Core (Extension), Help


F2bTechnician

activity notesReacting metals with acids

EquipmentFor each group:

� four test tubes, bungs and rack� 0.4 mol/dm3 hydrochloric acid� metals: iron filings, magnesium ribbon, small pieces of granulated zinc,

copper turnings� spatulas� Bunsen burner and spills


For your informationRunning the activityShow pupils the technique of testing for hydrogen. This can be done byemphasising the technique during the demonstration of the reaction betweencalcium and water in Activity F2a.

Ask pupils to design their tables for recording observations before starting thepractical.

Emphasise the outcome that copper does not react with dilute acids.

Core: Follow instructions on Activity sheet F2b.

Help: This has a table to record observations and simplified questions.

Extension: Additional questions are available at the bottom of the core sheet.

Expected outcomesCore: Magnesium reacts quickly with dilute acid and produces enoughhydrogen to give a definite ‘pop’. Zinc fizzes less vigorously, iron producesbubbles slowly.

Help: As core, with less emphasis on Sc1.

Extension: Pupils have the opportunity of practising planning and predictingskills for Sc1.

PitfallsThe QCA Scheme of Work recommends that the acids used are atconcentrations of 0.4 mol/dm3. This is lower than was traditionally used forthese experiments.

The reactions of iron and zinc are slow at this concentration. The hydrogen‘pop’ test is unlikely to work satisfactorily because only small quantities ofhydrogen are evolved. Pupils need to look carefully to compare the rate ofbubbles of hydrogen evolved.

Safety notesWear eye protection. Wash any acid splashes off skin immediately.


Type Purpose DifferentiationPractical Pupils carry out an experiment to react metals with dilute hydrochloric acid. Core (Extension), Help


F2bActivity

CoreReacting metals with acids

Many metals react with acids. In this experiment you are going to look at how quickly four different metals react with dilute hydrochloric acid.

Obtaining evidence

1 Design a table to present yourobservations.

2 Add 2 cm depth of acid to four testtubes in a test tube rack.

3 Set up a lighted Bunsen burner andhave a bung and spill ready to testfor hydrogen.

4 Add a small piece of magnesium tothe first test tube.

5 Record the observations you see.Test the gas to see if it is hydrogen.

6 Investigate zinc, iron and copper inthe same way.


1 Put the four metals in order from ‘most reactive’ to ‘least reactive’.2 Write a full list of reactivity to include these metals: sodium, gold,

calcium, magnesium, potassium, iron, copper and zinc.3 The general equation for reacting metals with hydrochloric acid is

metal + hydrochloric acid → metal chloride + hydrogen

Write word equations for the reactions of zinc and iron with hydrochloric acid.

4 Sulphuric acid reacts with metals to make a metal sulphate and hydrogen.

Write word equations for zinc and iron reacting with sulphuric acid.

5 a Predict which of the four metals (magnesium, zinc, iron, copper) gives out mostenergy when it reacts with acid. Explain your reasoning.

b Give an outline of an experiment that would show whether your prediction is right.


magnesium

hydrochloric acid

Hydrogen pops when lit.

bunglighted spill

Wear eyeprotection.

Take care when handlingacid. Wash

any acid splashes withlots of water.

Extension


F2bActivity

HelpReacting metals with acids

Use this sheet to record your observations.

Obtaining evidence

Use this table to record what you see.


1 Put these metals in order ‘most reactive’ to ‘least reactive’.

copper magnesium iron zinc gold sodium

2 This is the equation for magnesium reacting with hydrochloric acid.

magnesium + hydrochloric acid → magnesium chloride + hydrogen

Complete the equations for zinc and iron.

zinc + hydrochloric acid → +

iron + hydrochloric acid → +


Metal Observations Did the gas go pop?

magnesium

copper

zinc

iron


F2cTeacher

activity notesRelatively reactive

Running the activityPupils allocate a ‘reactivity rating’ for the 24 common metals in the database,according to the questions in the database that relate to reactivity (see Activitysheets). The teacher can modify the database as required (e.g. the last column hiddenfor Core and Help, or use the sort function to hide the non-metals for Help).

Core: There are three questions to apply to the database, giving a rating of 1 (mostreactive) to 4 (least reactive). Pupils should use the ‘Sort’ function to organise themetals into the categories.

Help: Pupils fill in their answers on the sheet, which shows them how many metalsbelong in each category.

Extension: There are four questions to apply to the database, the extra questionintroduces the idea that carbon has its place in the reactivity series. Pupils rate thecommon metals on a scale of 1–5, deciding for themselves what combination ofanswers defines each category.

This PC-based activity uses a Microsoft® Excel spreadsheet available on the CD-ROMthat accompanies this pack.

Other relevant materialSkill sheet 26: Designing a spreadsheet

Expected outcomesPupils use data stored in the database to categorise metals according to theirreactivity.

PitfallsMake sure the pupils have selected the most common metals. You may like to showthem how to split the screen, or how to hide columns, so that they can see whichmetal goes with which combination of answers. With less IT literate pupils, you couldhide the irrelevant columns in advance, or adapt the spreadsheet to show onlymetals.

AnswersCore:

1 1: Lithium, sodium, potassium, rubidium, caesium, strontium, barium.2: Beryllium, magnesium, calcium.3: Aluminium, tin, lead, chromium, manganese, iron, nickel, cobalt, zinc.4: Copper, silver, platinum, gold, mercury.

Help:

1 See Core 1 above.

Extension:

1 1 = lithium, sodium, potassium, rubidium, caesium, strontium, barium.2 = beryllium, magnesium, calcium.3 = aluminium.4 = tin, lead, chromium, manganese, iron, nickel, cobalt, zinc.5 = copper, silver, platinum, gold, mercury.

2 The more reactive metals are in group I and group II.


Type Purpose DifferentiationICT Pupils use a database to work out a reactivity series of metals. Core, Help, Extension


F2cActivity

CoreRelatively reactive

You are going to give 24 common metals a ‘reactivity rating’ on a 1 to 4 scale, where 1 is most reactive and 4 is least reactive.

You are going to use a database. You are only to work on common metals, so use a filter to select the common metals. There are three questions that relate to reactivity. The answers to these questions are used to decide the rating.

1 Put each of the 24 common metals into one of the four categories.


Sheet 1 of 1

ActivityCoreF2c Relatively reactive


Reactivity Does it have to be Does it react in Does it react with rating stored under oil or cold water within dilute hydrochloric acid

in an inert gas? five minutes? within five minutes?

1 yes yes yes

2 no yes yes

3 no no yes

4 no no no

You are going to give 24 common metals a ‘reactivity rating’ on a 1 to 4 scale, where 1 is most reactive and 4 is least reactive.

You are going to use a database. You are only to work on common metals, so use a filter to select the common metals. There are three questions that relate to reactivity. The answers to these questions are used to decide the rating.

1 Put each of the 24 common metals into one of the four categories.

Reactivity Does it have to be Does it react in Does it react with rating stored under oil or cold water within dilute hydrochloric acid

in an inert gas? five minutes? within five minutes?

1 yes yes yes

2 no yes yes

3 no no yes

4 no no no


F2cActivity

HelpRelatively reactive

You are going to give 24 common metals a score to show how reactive they are.

A score of 1 is the most reactive.

A score of 4 is the least reactive.

You are going to use a database. You are only to work on common metals.

There are three questions that relate to reactivity. The answers to these questions are used to decide the score.

1 Select the metals which have ‘yes’ in the ‘Is it a common metal?’ column.2 Use the filters to pick out the metals with each score. Use the table above

to help you.

1 Record your answers by writing the names of the metals in this score chart:


Score Does it have to be Does it react in Does it react with stored under oil or cold water within dilute hydrochloric acid in an inert gas? five minutes? within five minutes?

1 yes yes yes

2 no yes yes

3 no no yes

4 no no no

Score 1 2 3 4

Metals with this score


F2cActivity

ExtensionRelatively reactive

You are going to decide on the relative reactivity of 24 common metals.

You are going to use a database. You are only to work oncommon metals. The database contains the answers to fourquestions about reactivity.

One of the questions mentions carbon. Even though carbon is nota metal, it is useful to place it in the reactivity series. Metals belowcarbon in the series can be extracted from their compounds byreaction with carbon.

Some metals cannot be extracted from their compounds bycarbon. These metals are above carbon in the reactivity series.

1 Use the database to allocate each of the common metals toone of five categories, where category 1 contains the mostreactive metals and category 5 contains the least reactivemetals.

2 Look at a periodic table while thinking about your fivecategories. Do you see any pattern?


Question Relatively Relatively more reactive less reactive

Does it have to be stored under oil or in an inert gas? yes no

Does it react in cold water within five minutes? yes no

Does it react with dilute hydrochloric acid within yes nofive minutes?

Could it be made from its compounds using carbon? no yes


F2dTeacher

activity notesElectrons in atoms

Running the activityAlthough the link between the periodic table and the arrangement of electrons in atoms isconsidered a KS4 topic, it (along with Activities F1c and F3c ) will allow access to part ofthe attainment target for EP in Sc3: ‘Recognising that differences in the properties ofmaterials relate to the nature of the particles within them’.

The activity is designed to be done by a pupil or a pair of pupils working alone, so moreassistance is provided than is usual for an Extension activity. Pupils can either work on thesheet itself or on an enlarged photocopy of the diagram. Alternatively they can draw theatoms on a separate piece of paper. Full answers are provided below, so that pupils canmark their own work.

Expected outcomesPupils should be able to recognise the patterns in electron arrangement and use thisinsight to answer questions 4 and 5.

PitfallsAtomic structure is a not a suitable topic for the great majority of Year 9 pupils, who needto concentrate on the KS3 curriculum.

Answers1 , 2

3 The number of electrons in the outer shell equals the group number for groups I–VII.

4 All their electron shells are full, even the outer one.

5 a Hydrogen has one electron in its outer shell and therefore belongs in group I.

b Hydrogen has one electron missing in its outer shell, and therefore belongs ingroup VII with the other elements that have one electron missing in their outershells.


Type Purpose DifferentiationPaper To cater for the interest in atoms that some, usually more able, pupils express in Year 9.

This activity encourages the pupil to make the link between the periodic table and thearrangement of electrons in atoms.

Extension

1

H

3

Li11

Na19

K

20

Ca

12

Mg

13

Al

14

Si

15

P

16

S

17

Cl

18

Ar

4

B

5

Be

6

C

7

N

8

O

9

0

F

10

Ne

2

HeI II III IV V VI VII


F2dActivity

ExtensionElectrons in atoms

You are going to work out the electron arrangement of the first 20 elements in the periodic table.

The rules for arranging electrons are as follows:

� The atomic number gives the number of protons and therefore the number of electrons.� Fill the ‘shells’ from the inside outwards.� The inner shell can take up to two electrons.� The second and third shells take up to eight electrons.

Remember: In any element, the number of protons equals the number of electrons.

1 Fill in the electrons for the first 10 elements. Two are done for you, so that you can check you are doing it correctly.

2 Group I has been labelled on the diagram above. Label the other groups: II, III, IV, V, VI, VII and 0.

3 Look at groups I to VII. Describe the relationship between the number of electrons in the outer shell and the group number.

4 Look at group 0. What do the atoms of the three elements in group 0 (helium, neon and argon) have in common?

5 In this version of the periodic table, hydrogen has been put in group I. However, some versions of the periodic table put hydrogen in group VII.

a Give one reason, based on its arrangement of electrons, why hydrogen should be in group I.

b Give one reason, based on its arrangement of electrons, why hydrogen should be in group VII.


1

H

3

Li11

Na19

K

20

Ca

12

Mg

13

Al

14

Si

15

P

16

S

17

Cl

18

Ar

4

Be

5

B

6

C

7

N

8

O

9

F

10

Ne

2

HeGroup I


F3aTeacher

activity notesDisplacement reactions

Running the activityPupils follow the Activity sheet. They establish whether copper or zinc is more reactive, before comparing magnesium to copper and zinc to copper.

Core: Pupils follow the instructions on the sheet and draw up their own table of results.

Help: The teacher shows pupils what to do, then they record their results and complete the equations on the Activity sheet.


Expected outcomesZinc displaces copper from copper sulphate solution. Brown copper will be seen; the blue solution of copper sulphate will get paler and the test tube will become warm. There is no reaction between copper and zinc sulphate solution.

Magnesium displaces copper from copper sulphate solution. Brown copper will be seen, the blue solution of copper sulphate will get paler and the test tube will become warm. There is no reaction between copper and magnesium sulphate solution.

Magnesium displaces zinc from zinc sulphate solution. There are no colour changes to be seen, but the test tube will become warm. There is no reaction between zinc and magnesium sulphate solution.

PitfallsPupils find displacement reactions very confusing and will need support to understand what they see.

Safety notesEye protection should be worn at all times. Any splashes should be immediately rinsed.

AnswersCore: 1 Zinc + copper sulphate, magnesium + copper sulphate, magnesium + zinc sulphate.

Colour changes and/or warming show this.2 no3 yes4 zinc5 Zinc + copper sulphate → copper + zinc sulphate6 magnesium7 Magnesium + copper sulphate → magnesium sulphate + copper8 magnesium9 Magnesium + zinc sulphate → magnesium sulphate + zinc

Help: 1 zinc2 Zinc + copper sulphate → copper + zinc sulphate3 Magnesium4 Magnesium + copper sulphate → magnesium sulphate + copper5 magnesium6 Magnesium + zinc sulphate → magnesium sulphate + zinc


Type Purpose DifferentiationPractical Pupils use test tube displacement reactions to investigate reactivity of three metals Core, Help


F3aTechnician

activity notesDisplacement reactions


� 6 test tubes� test tube rack

For the class:

� 4 × 250 cm3 0.5 mol/dm3 copper(II) sulphate solution, with labelled small beakerand graduated plastic dropping pipette

� 4 × 250 cm3 0.5 mol/dm3 magnesium sulphate solution, with labelled small beakerand graduated plastic dropping pipette

� 4 × 250 cm3 0.5 mol/dm3 zinc sulphate solution, with labelled small beaker andgraduated plastic dropping pipette

� 4 small pots of copper turnings, with spatula

� 4 small pots of magnesium turnings, with spatula

� 4 small pots of zinc turnings, with spatula


For your informationRunning the activityPupils follow the Activity sheet. They establish whether copper or zinc is morereactive, before comparing magnesium to copper and zinc to copper.

Core: Pupils follow the instructions on the sheet and draw up their own table ofresults.

Help: The teacher shows pupils what to do, then they record their results and completethe equations on the Activity sheet.

Expected outcomesZinc displaces copper from copper sulphate solution. Brown copper will be seen; theblue solution of copper sulphate will get paler and the test tube will become warm.There is no reaction between copper and zinc sulphate solution.

Magnesium displaces copper from copper sulphate solution. Brown copper will beseen, the blue solution of copper sulphate will get paler and the test tube will becomewarm. There is no reaction between copper and magnesium sulphate solution.

Magnesium displaces zinc from zinc sulphate solution. There are no colour changes tobe seen, but the test tube will become warm. There is no reaction between zinc andmagnesium sulphate solution.

PitfallsPupils find displacement reactions very confusing and will need support tounderstand what they see.

Safety notesEye protection should be worn at all times. Any splashes should be immediatelyrinsed.


Type Purpose DifferentiationPractical Pupils use test tube displacement reactions to investigate reactivity of three metals. Core, Help


F3aActivity

CoreDisplacement reactions

You are going to carry out some displacement reactions todecide which metal is more reactive. You are going to use‘turnings’, which are small, curved pieces of metal.

Remember – In a displacement reaction, the more reactive metaldisplaces the less reactive metal from its compound.

Obtaining evidence

You are going to try reacting zinc with copper sulphatesolution, then copper with zinc sulphate solution.

1 Draw up a table to record your observations.2 Put about 2 cm3 of copper sulphate solution in

a test tube.3 Add 1 small spatula of zinc turnings.4 Write down your observations in your table.5 Put about 2 cm3 of zinc sulphate solution in another test tube.6 Add 1 small spatula of copper turnings.7 Write down your observations in your table.

Now you are going to try reacting magnesium with coppersulphate solution, then copper with magnesium sulphatesolution.

8 Draw up a table to record your results.9 Carry out the tests as you did in steps 2 to 7 above.

Finally you are going to try reacting first zinc with magnesiumsulphate solution, then magnesium with zinc sulphate solution.

10 Draw up a table to record your results.11 Carry out the tests as you did in steps 2 to 7 above.


1 In which test tubes did a chemical reaction take place? Howdid you know?

2 Did copper displace zinc from the zinc sulphate?3 Did zinc displace copper from the copper sulphate?4 Which is the more reactive metal, zinc or copper?5 Write a word equation for the reaction that happened.6 Which is the more reactive metal, copper or magnesium?7 Write a word equation for the reaction that showed this.8 Which is the more reactive metal, zinc or magnesium?9 Write a word equation for the reaction that showed this.


Wear eyeprotection.

Wash anysplashes ofsolutions off

your skin immediately.

copper sulphatezinc turnings


You are going to carry out some displacement reactions todecide which metal is more reactive. You are going to use‘turnings’, which are small, curved pieces of metal.

Your teacher will show you what to do. Record your observationsand fill in the answers below.Remember – In a displacement reaction, the more reactive metaldisplaces the less reactive metal from its compound.

1 Which is the more reactive metal, zinc or copper?

2 Complete this word equation: zinc + copper sulphate → +

3 Which is the more reactive metal, magnesium or copper?

4 Complete this word equation: magnesium + copper sulphate → +

5 Which is the more reactive metal, zinc or magnesium?

6 Complete this word equation: magnesium + zinc sulphate → +

F3aActivity

HelpDisplacement reactions


Reactants Observations Which metal displaced which?

zinc and copper

zinc copper sulphate solution

copper zinc sulphate solution

magnesium and copper

magnesium copper sulphate solution

copper magnesium sulphate solution

zinc and magnesium

zinc magnesium sulphate solution

magnesium zinc sulphate solution


F3bTeacher

activity notesDisplacement in action

Running the activityPupils set up the experiment as shown on Activity sheet F3b.

Pupils work in groups to explain their ideas about what is happening. They need to linktheir observations of copper plating the zinc strip to the idea that zinc is more reactivethan copper. More able pupils may be encouraged to think about what would happen tothe colour of the copper sulphate solution over time.

Pupils should then consider the two descriptions in the boxes and discuss the questions asa group.

Expected outcomesThe zinc strip becomes coated with copper. If left for longer, the copper may start to form clumps and sink to the bottom of the tube. Over time, the colour of the solution may fade.

Safety notesWear eye protection and wash any splashes off skin immediately.

Answers1 Zinc cannot be plated onto iron by displacement. Zinc is more reactive than iron.

2 Silver can be plated onto iron by displacement. Silver is less reactive than iron.


Type Purpose DifferentiationPractical Pupils look at zinc displacing copper and consider other applications of displacement. Core


F3bTechnician

activity notesDisplacement in action


� boiling tube and rack� 0.4 mol/dm3 copper sulphate solution� zinc strip approx same length as boiling tube and narrow enough to fit in boiling tube

Zinc strip should be cleaned shortly before use by dipping into dilute hydrochloric acid, thendilute sodium hydroxide and then rinsing.

Strips can be reused by washing and treating with dilute acid as above.

For your informationRunning the activityPupils set up the experiment as shown on Activity sheet F3b.

Pupils work in groups to explain their ideas about what is happening. They need to link theirobservations of copper plating the zinc strip to the idea that zinc is more reactive thancopper. More able pupils may be encouraged to think about what would happen to the colourof the copper sulphate solution over time.

Pupils should then consider the two descriptions in the boxes and discuss the questions as agroup.

Expected outcomesThe zinc strip becomes coated with copper. If left for longer, the copper may start to formclumps and sink to the bottom of the tube. Over time, the colour of the solution may fade.

Safety notesWear eye protection and wash any splashes off skin immediately.


Type Purpose DifferentiationPractical Pupils look at zinc displacing copper and consider other applications of displacement. Core


F3bActivity

CoreDisplacement in action

Displacement reactions can be used to put a thin coating ofone metal on another. You are going to see how this works.

1 Fill a boiling tube about half full with copper sulphate solution.2 Stand a zinc strip in the tube.3 Look at the strip after a few minutes.4 Work as a group to think about what you see.

Make a large coloured diagram of yourobservations. Write explanations in bubblesaround your diagram to explain the changes.Your explanation should include:

� a word equation� ideas about reactivity of metals� ideas about displacement.

5 Look at the boxes below. Work as a group toanswer the questions.


Wear eyeprotection.

Wash anysplashes of copper

sulphate solution offyour skin immediately.

copper sulphate

strip of zinc

Galvanised iron is used to make barriers and fences. It ismade by putting a thin coating of zinc on iron. Putting athin layer of one metal on another metal is called plating.

1 Can iron be plated with zinc by dipping iron intozinc sulphate solution?

Explain your reasoning.

Silver plated jewellery is made by putting a thin plating of silver on another metal, such as iron.

2 Can iron be plated with silver by dipping iron into a solution of a silver salt?

Explain your reasoning.


F3cTeacher

activity notesAtoms and ions

Running the activityIt is assumed that these rare pupils will be working alone. However, the activitymay generate more questions than it answers!

Expected outcomesThe pupil understands the sheet and can manage the questions without furtherhelp. If they need more help, they are probably not working at the necessarylevel.

Answers1 a A positive ion is an atom that has lost electrons.

b Na+ is an atom of sodium that has lost one electron and is now a positiveion.

c Al3+ is an atom of aluminium that has lost three electrons and is now apositive ion.

2 Lithium + beryllium ions → lithium ions + beryllium2Li + Be2+ → 2Li+ + Be


Type Purpose DifferentiationPaper To give the most able of able pupils extension work which will help satisfy their

curiosity about what is happening during reactions, using the example of adisplacement reaction

Extension

+3 +3 +4

2 electrons from lithium beryllium ion


F3cActivity

ExtensionAtoms and ions

You are going to learn about atoms losing or gaining electrons during reactions.

Read the following information carefully, then answer the questions.


Atoms and ionsIn sodium metal, each atom of sodium has 11 electrons.

An atom of sodium in a compoundlike sodium chloride or sodium oxide has lost anelectron. It still has 11 protons in its nucleus, butit now has only 10 electrons.

Each proton has a charge of +1, so the nucleushas a charge of +11. Each electron has a chargeof –1, so the electrons have a charge of –10.

Overall the atom has a charge of+1. We call a charged atom an ion.Sodium atoms in compounds are+1 ions. These are written as Na+.

Reactive metals, like sodium, arenot found in nature. All the sodium atoms arefound as sodium ions in compounds. Sodiumatoms always react to lose their outer electronsand form sodium ions.

In aluminium metal, the atomshave 13 electrons each. Inaluminium compounds, all 3 outerelectrons have been lost. Thismeans the aluminium compoundcontains +3 ions.

Displacement reactionsIf you put a sodium compound with aluminiummetal, nothing happens. Aluminium is lessreactive than sodium, so aluminium cannotdisplace sodium from its compound.

If you put an aluminium compound with sodium,a reaction occurs. Energy is given out, a sodiumcompound is made and the aluminium ends upas the metal.

sodium + aluminium ions → sodium + aluminium 3Na + Al3+ → 3Na+ + Al

3 electrons from sodium → aluminium

You can think of displacement reactions as acompetition between metals to become ions, bygetting rid of ‘unwanted’ outer electrons. Themore reactive a metal, the more effective it is atgetting rid of these outer electrons.

In the example above, sodium is more reactivethan aluminium, so aluminium ends up with the‘unwanted’ electrons.

+11

+11

1 electron 'lost'

+13

3 electrons 'lost'

1 Explain, in your own words, what these scientific terms mean:

a positive ion b Na+ c Al3+

2 Lithium (Li) has atomic number 3, so it has one electron in its outer shell. Lithiumloses its one outer electron when it becomes a compound.

Beryllium (Be) has atomic number 4, so it has two electrons in its outer shell. It losesits two outer electrons when it becomes a compound.

Lithium is more reactive than beryllium. What will happen when lithium metal ismixed with a beryllium compound?

Represent this reaction using a word equation, a balanced symbol equation and adiagram.

F-Activities.qxd 21-Jul-04 3:49 PM Page 13

F4aTeacher

activity notesUsing reactivity data

Running the activityPupils need experience of the types of data handling question they may encounter in the SATfor KS3 Science. This question leads pupils through an analysis of two sets of data.

Pupils use data from two experiments to work out a reactivity series.

Core: The Activity sheet leads pupils through the argument.

Extension: This extends the task to include asking pupils to think about ideas of energychanges in the reaction.


Expected outcomesPupils realise that Justin’s data cannot give a full reactivity series, but that Vishal’s can. They deduce a reactivity series based on Vishal’s data.

PitfallsThere is a problem in that the larger the temperature rise, the less reactive the metal (as compared to magnesium). This will confuse many pupils, and the teacher should be able to give guidance.

ICT opportunitiesIt would be possible to set up a spreadsheet for the results and ask pupils to produce bar charts to display them.

AnswersCore:

1 B (with zinc) and C (with magnesium). There is a new substance being made because bubbles are observed.

2 a More bubbles/faster bubbles (of hydrogen).b Zinc is less reactive than magnesium. The other three are less reactive than zinc.

3 A temperature change happens when a chemical reaction occurs (due to energy beinggiven out).

4 a Magnesium produces the largest temperature change.b Magnesium, zinc, iron, lead, copper.

Extension:

5 magnesium + hydrochloric acid → magnesium chloride + hydrogenzinc + hydrochloric acid → zinc chloride + hydrogen

6 magnesium + zinc nitrate → zinc + magnesium nitrateMg + Zn(NO3)2 → Zn + Mg(NO3)2

7 More reactive metals give out more energy when they react, leading to bigger temperaturechanges. Very able pupils may appreciate that it is the difference in reactivity between thetwo metals that determines the amount of energy given out.


Type Purpose DifferentiationPaper Pupils use data from two experiments, one involving temperature change, to rank metals

in order of reactivity.Core (Extension)


F4aActivity

CoreUsing reactivity data

You are going to use secondary data from two experiments to work out a reactivity series.


Experiment 1Justin added a spatula of metalfilings to 2 cm3 of dilutehydrochloric acid. He observedthat bubbles were producedimmediately. The diagram showswhat Justin observed.

Experiment 2Vishal added a spatula ofmagnesium powder to fivedifferent salt solutions andmeasured the temperature rise.

1 Study Justin’s results. Explainhow you know that there is a chemical reaction occurringin some of the test tubes butnot others.

2 a How do Justin’s resultsshow that magnesium isthe most reactive metal?

b What can you conclude about the reactivity of the other metals from Justin’s results?

3 Study Vishal’s results. Explain how you know that there is a chemical reactionoccurring in some of the test tubes but not others.

4 a How do Vishal’s results show that magnesium is the most reactive metal?b Use Vishal’s results to put the five metals in order ‘most reactive’ to ‘least reactive’.

5 Write a word equation for one of the reactions in Justin’s experiment.6 Write a word and symbol equation for the reaction between

magnesium and zinc nitrate in Vishal’s experiment. Use the symbols in the box to help you.

7 Explain, using ideas about chemical change and metal reactivity, why different metalsgave different temperature changes in Vishal’s experiment.


iron zinc magnesium lead copper

Test tube Type of salt Temperature (°C)

A iron nitrate 36

B zinc nitrate 15

C magnesium nitrate 0

D lead nitrate 41

E copper nitrate 46

Extension

Mg(NO3)2

Zn(NO3)2


F5aTeacher

activity notesUses of metals

Running the activityFinding relevant information is very time consuming. Give pupils the briefing cards at theend of lesson F4 and ask them to carry our web searches for homework. Alternatively, providepacks for each group containing relevant printouts of suitable websites. Properties andprocesses can be found in standard textbooks. See below for suggested websites.

Tell pupils that more than one group is carrying out research into the same metal so it isimportant that they stick to the questions they are asked to look at.

Pupils can present their information in a number of ways. They can be given OHTs to use asvisual aids to a short talk, or they can make posters, leaflets or magazines. If time allows theycan produce their presentation electronically.

Ask each group to make a short, timed presentation to the rest of the class. If pupils areconfident, you can formalise this by having an orange and red card system, as is used informal public speaking contests. When the speaker strays from the point, other pupils holdup an orange card and a red card means ‘out of time.’

Other relevant materialSkill sheet 4: Web searches

F5a Resource

PitfallsWarn pupils not to copy out large amounts of information they do not understand. They donot need, for example to understand the processes in the Blast furnace or electrolysis ofaluminium. They need to know in outline how the metals are extracted.

ICT opportunitiesIt would be possible to set up a database to present properties of metals. Pupils may also liketo present the properties in electronically produced tables.

Useful websites…

Gold: Nine carat gold websiteCambrian GoldFields Ltd: gold authentication(this site includes information about hallmarking)

Iron: Steel Recycling Institute

Copper: Schoolscience

Element properties: WebElements Periodic Table


Type Purpose DifferentiationDiscussion Pupils carry out research about a metal. They present their findings to the whole class

as part of a presentation activity.CoreResource (C, H, E)







F5aActivity

CoreUses of metals

You are going to work in a group to research and present information about a metal.

1 Look at the briefing card your teacher gives you. It will guide your research on a particular metal.

Think about ...

� How will you divide up the tasks in your group?� How will you research your metal? You can use books or carry out web searches.� You need to make sure not to copy out information you do not understand – some of

the information you will find will be too technical. Use only the interesting aspects thatwill appeal to other people in your class. You might be able to find out some ‘Funfacts’ about your metal that you can use.

� How will you present the information to make it as interesting as possible for the restof the class? You might decide to use charts, graphs, tables, posters, OHTs or writeyour presentation using a computer. You might consider putting your researchtogether to make a booklet.

Sheet 1 of 1

Sheet 1 of 1


ActivityCoreF5a Uses of metals

You are going to work in a group to research and present information about a metal.

1 Look at the briefing card your teacher gives you. It will guide your research on a particular metal.

Think about ...

� How will you divide up the tasks in your group?� How will you research your metal? You can use books or carry out web searches.� You need to make sure not to copy out information you do not understand – some of

the information you will find will be too technical. Use only the interesting aspects thatwill appeal to other people in your class. You might be able to find out some ‘Funfacts’ about your metal that you can use.

� How will you present the information to make it as interesting as possible for the restof the class? You might decide to use charts, graphs, tables, posters, OHTs or writeyour presentation using a computer. You might consider putting your researchtogether to make a booklet.



F5aActivityResourceMetals in action


Help

GOLD

Things to find out

1 What is gold used for apart fromjewellery?

2 What are the properties of gold?3 Try to find out about hallmarking

gold.

Help

IRON

Things to find out

1 What is iron used for?2 What are the properties of iron? 3 How is the iron in old cars

collected and re-used?

Core

ALUMINIUM

1 Research the properties and usesof aluminium.

2 Find out why aluminium does notcorrode, even though it is a veryreactive metal.

Core

IRON

1 Find out what raw materials areused to make iron and what theprocess is called.

2 What is the difference betweeniron and steel? Why is steel betterthan iron for most uses?

Extension

ALUMINIUM

1 Find out why the extraction ofaluminium uses a great deal offuel and so is very expensive.

2 Find out how aluminium isrecycled.

Extension

COPPER

1 Find out about the properties anduses of copper.

2 Find out why copper for electricalcables needs to be very pure, andhow copper is purified (you do notneed to go into a lot of detail).


F6aTeacher

activity notesVariables in rusting

Running the activityPupils look at the experiment and answer the questions on the sheet for Activity F6a. Theyconsider whether the results of the experiments support the stated conclusions.

Expected outcomesBoth air and water are needed for iron to rust, so they are interacting variables. Iron incontact with air or water alone does not rust. Salty water speeds up rusting. Greasing the ironor wrapping it in zinc stops rusting.

Pupils may be interested to note that the zinc does not need to coat the iron – as long as theiron is touching the zinc, rust prevention will work. This principle is used to protectexpensive engineered structures, e.g. oil rigs and ships, which have replaceable blocks of zincbolted onto them. The zinc corrodes away instead of the iron. This is called ‘sacrificialprotection’.

PitfallsAfter some time the nails in all tubes will rust. Water and air will penetrate the grease.

Answers

1 Both water and air are needed. Iron in test tubes with air or water alone does not rust, butin test tube 3 it goes rusty when it is in contact with both.

2 Grease prevents air or water getting to the iron so it cannot go rusty.

3 Iron in salty water is more rusty than in just water. The iron nail in test tube 6 has notgone rusty.

4 Put iron nails wrapped in different metals in water and see how much they rust. Metalstested should include at least two more reactive metals (e.g. magnesium, zinc) and oneless reactive (copper). The control should be iron in water with no metal.

5


Type Purpose DifferentiationPractical Pupils analyse the results of an experiment set up to investigate rusting. Core

Test tube Number of variables Independentvariables

1 – –

2 1 water

3 – –

4 3 –

5 – salt, air and water

6 2 zinc, air and water


F6aTechnician

activity notesVariables in rusting


Test tubes set up and labelled as in the diagram. This will need to be set up one weekbefore it is needed to allow it time to work. If necessary, cheat by using clean nails intubes 1, 2, 4 and 6 and rusty nails in tubes 3 and 5. The nail in the salty water shouldbe much rustier.

The drying agent in tube 1 can be either dried silica gel or calcium oxide. The waterin tube 2 must be deoxygenated by simmering for 15–20. Add oil to exclude air fromthe upper surface.

Use a thick coat of vaseline for grease. The nails in tubes 3–6 should be half in andhalf out of the water.

New iron nails should be used. The nails should be soaked in ethanol/methylatedspirits to cut any grease on the surface (which is added to prevent rusting whilestored), then dried on the day of the experiment.

Labels: label each tube with numbers 1–6.

For your informationRunning the activityPupils look at the experiment and answer the questions on the sheet for Activity F6a.They consider whether the results of the experiments support the stated conclusions.

Expected outcomesBoth air and water are needed for iron to rust, so they are interacting variables. Ironin contact with air or water alone does not rust. Salty water speeds up rusting.Greasing the iron or wrapping it in zinc stops rusting.

Pupils may be interested to note that the zinc does not need to coat the iron – as longas the iron is touching the zinc, rust prevention will work. This principle is used toprotect expensive engineered structures, e.g. oil rigs and ships, which havereplaceable blocks of zinc bolted onto them. The zinc corrodes away instead of theiron. This is called ‘sacrificial protection’.

PitfallsAfter some time the nails in all tubes will rust. Water and air will penetrate the grease.


Type Purpose DifferentiationPractical Pupils analyse the results of an experiment set up to investigate rusting. Core

dryair

1

ironnail

dryingagent

water+

no air

2

boiledwater

oil

air+

water

3

greasednail

4

greasednail

saltywater

5

saltywater

zinc

6

zinc


F6aActivity

CoreVariables in rusting

You are going to look at the results of a rusting experiment that has been set up for you.

1 Ashak carried out this experiment and wrote this conclusion.

1 Do you agree with Ashak? What evidencedoes he have for his conclusion?

2 Petra wrote these conclusions in her book.

2 Petra has not finished explaining why grease stops rusting in test tube 4. Finish the explanation for her.

3 What evidence supports Petra’s conclusions for test tubes 5 and 6?4 Outline how you would go about proving that metals more reactive

than iron stop iron rusting but less reactive metals do not.

5 Copy and complete the table to show which independentvariables are interacting in eachtest tube.


dryair

1

ironnail

dryingagent

water+

no air

2

boiledwater

oil

air+

water

3

greasednail

4

greasednail

saltywater

5

saltywater

zinc

6

zinc

Conclusion 1From looking at test tubes 1, 2and 3 I can tell that iron needsboth air and water to make it rust.

Test tube 4 proves that using grease stops iron rusting. I think this is because ...

Test tube 5 proves that salty water makes iron rust faster.

Test tube 6 proves that zinc stops iron rusting. Zinc is more reactive than iron.I think that all more reactive metals must stop iron going rusty.

Test tube Number of Independent variables variables

1 1 air

2

3 2 air and water



F1 PlenariesLosing that shine

Review learning� Pupils make four or five key fact cards about key facts they have learned

during the lesson.

� Less able pupils can copy the facts from the ‘For your notes’ section ofthe textbook page.

� More able pupils should write their own fact cards based on their ownideas of which facts are important. Encourage them to include wordequations.

� Pupils work in pairs and test each other to see how many key facts theycan remember from their cards.

� Equipment: approximately 4 pieces of paper or card made by cutting A4into 6 or 8 pieces.

Sharing responses� Write the question on the right on the board. Invite pupils from

different working groups to suggest ideas.

� Make notes to summarise their ideas. They should think about both howthe reactivity of the metal is important as well as essential conditions,e.g. air and water. More able pupils should consider what conditionscause more rapid corrosion, e.g. salt on roads, and how metals aretreated to slow corrosion, e.g. painting, oiling, alloying etc.

Group feedback� Pupils combine into larger working groups to compare their answers to

Activity F1b.

� A spokesperson refers any differences in opinion that are not resolvedwithin the group to the whole class for discussion.

Word game� This plenary is particularly suitable for use with less able pupils.

� Pupils complete the pupil sheet by filling in missing words. This coversthe main teaching points from the Green book.

Looking ahead� Show pupils the photograph of the iron bridge. Ask them to think about

other ways that the iron is attacked, apart from its reaction with oxygen.Ask them to work in groups to jot down their ideas to feed into a classplenary.

� Pupils may have ideas about physical weathering from geography, andmay suggest that salt (from winter spreading) and acid (from the rain)attack the iron. This leads into ideas about metals reacting with acidsnext lesson.

QuestionWhy do metals corrode atdifferent rates?

➔ Pupil sheet

Answers to word gameoxygen; faster, energy; ironoxide, air/water (eitherorder)



Review learning

Pupils make key factcards and use them totest each other.

Sharing responses

Whole-class discussionsummarising ideas aboutwhat causes metals tocorrode at different rates.

Group feedback

Pupils combine into largergroups to compare theirresponses to Activity F1b.

Word game

Pupils completesentences with missingwords to show key pointsof lesson.

Looking ahead

Pupils think about other substancesthat react with metals using thecontext of an iron bridge. Catalyst Interactive Presentations 3

F-Plenaries.qxd 08-Jun-04 1:11 PM Page 1

F1 PlenariesLosing that shine

Word game

Use information you have learned in this lesson to fill in the missing words.

Choose from these words:

air energy faster iron oxide oxygen water

Metals lose their shine when they react with in the airto make metal oxides.

More reactive metals react than less reactive metals.

Very reactive metals give out a lot of when they react.

Iron rusts when it reacts with oxygen. The chemical name for rust is

Iron needs and

to make it rust.

Sheet 1 of 1

Sheet 1 of 1


PlenariesF1 Losing that shine

Word game

Use information you have learned in this lesson to fill in the missing words.

Choose from these words:

air energy faster iron oxide oxygen water

Metals lose their shine when they react with in the airto make metal oxides.

More reactive metals react than less reactive metals.

Very reactive metals give out a lot of when they react.

Iron rusts when it reacts with oxygen. The chemical name for rust is

Iron needs and

to make it rust.




F2 PlenariesCorrosive liquids

Review learning� Pupils work in pairs to decide whether the statements on

the pupil sheet are true or false.

� Pupils combine with another pair to make a larger groupand compare responses.

� Check agreement with the whole class by plenary or byholding up true/false cards to teacher.

Sharing responses� Pupils combine into groups to compare their

observations and answers to the questions from Activity F2b.

� Each group chooses a spokesperson who raises any issuesto a short, whole-class plenary.

Group feedback� Show pupils the bottles of some of the metals and acids

they have used during the lesson. (NB pupils should nottouch the bottles.)

� Ask different groups to produce instructions on how tostore and handle each substance safely.

� A spokesperson feeds back and summarises their pointson the board.

Word game� Pupils work out the answers to the clues on the

Pupil sheet.

� They then make up descriptions of different metals.

� They read their description to their partner who has totry to guess the metal.

Looking ahead� Write on the board the list of metals in order of reactivity

from Activity F2b.

� As a whole-class discussion, ask pupils to identify metalswith particular properties, e.g. which metals corrodefastest, do not react with acids, react slowly with acids,react with water etc.

� Develop the idea that the reactivity of metal can be usedto make predictions about how the metals behave in newsituations that the pupils have not yet tested.

➔ Pupil sheet

Answers1 true; 2 true; 3 false; 4 false; 5 true

Equipmentbottles of the following, clearly showinghazard warning label: sodium, calcium,zinc (powder has flammable label), dil.sulphuric acid, dil. hydrochloric acid

➔ Pupil sheet

AnswersIron; potassium


Review learning

True/false quiz.

Sharing responses

Pupils work in groups todiscuss the outcomes ofActivity F2b.

Group feedback

Whole group discussionrelating to safetyprecautions when workingwith metals and acids.

Word game

Play ‘What am I?’ to guessthe metal.

Looking ahead

Class discussion abouttrends in reactivity.



Review learning

Decide whether the following statements are true or false.

1 All metals react with acids.

2 When metals react with acids they make a salt and hydrogen.

3 Calcium will react with hydrochloric acid to make calciumsulphate and hydrogen.

4 Shiny copper will go dull faster than shiny iron will go dull.

5 Goggles must always be worn when we handle acids.

Sheet 1 of 1

Sheet 1 of 1


PlenariesF2 Corrosive liquids

Review learning

Decide whether the following statements are true or false.

1 All metals react with acids.

2 When metals react with acids they make a salt and hydrogen.

3 Calcium will react with hydrochloric acid to make calciumsulphate and hydrogen.

4 Shiny copper will go dull faster than shiny iron will go dull.

5 Goggles must always be worn when we handle acids.



Word game

1 Work in pairs. Which metal are these descriptions about?

2 Make up your own descriptions of some other metals and see if your partner can guess what they are.


Sheet 1 of 1

Sheet 1 of 1


PlenariesF2 Corrosive liquids


I am a shiny grey metal. I go red-brown when I reactslowly with oxygen in the air. I also react slowly with acidsto make bubbles of hydrogen. What am I?

I am a soft metal and I am more reactive than sodium. Ireact very quickly with water and oxygen. What am I?

Word game

1 Work in pairs. Which metal are these descriptions about?

2 Make up your own descriptions of some other metals and see if your partner can guess what they are.

I am a shiny grey metal. I go red-brown when I reactslowly with oxygen in the air. I also react slowly with acidsto make bubbles of hydrogen. What am I?

I am a soft metal and I am more reactive than sodium. Ireact very quickly with water and oxygen. What am I?



F3 PlenariesChanging places

Review learning� Pupils use ‘yes’ and ‘no’ cards and hold them up to the

teacher in response to questions.

� Write the order of reactivity on the board and shout outpairs of metals and solutions, e.g. ‘copper and zincsulphate.’

� Pupils hold up cards to say ‘yes’ a reaction will happen,or ‘no’ it will not.

Sharing responses� Pupils combine into groups to discuss the outcomes of

Activity F3a.

� Ask pupils to think about why experiments with negativeresults, i.e. where reactions do not happen, are importantwhen we draw conclusions.

� Ask a spokesperson to feed back ideas to the rest of theclass.

Group feedback� Pupils make short presentations to show their ideas

about the zinc plating reaction in Activity F3b.

� This can either be run with a spokesperson talking to theclass, or two groups combining to show their ideas toeach other.

Word game� Pupils work out the anagrams on the Pupil sheet.

� Pupils make an anagram and a clue to try on each other.

Looking ahead� Ask pupils to work in groups to suggest one metal that

would displace all the metals that they have used todayand one that would not.

� Make a list on the board of the pupils’ suggestions. Askother groups if they agree.

Order of reactivitymagnesium; zinc; iron; copper

➔ Pupil sheet

Answersdisplacement; magnesium; gold; zinc;sulphate; zinc sulphate


Review learning

Game to predict if areaction will happenbetween named pairs ofmetals and metalcompounds.

Sharing responses

Pupils feed back theiroutcomes of Activity F3aand discuss why negativeresults are important inexperiments.

Group feedback

Groups make shortpresentations to show theirideas about displacementfrom Activity F3b.

Word game

Anagram game.

Looking ahead

Pupils are asked to suggestone metal that woulddisplace all the metals used today, and one thatwould not.


F3 PlenariesChanging places

Word game

1 Rearrange the letters to find the correct words.

ICDANTSPEMLE happens when metals react with metal salts.

MESNMIUAG is a metal that can displace iron but not calcium.

OLGD is a metal that cannot displace any other metal.

INCZ + iron UHELTASP → INCZ UHELTASP + iron

2 Make up some other clues and see if your friends can workthem out.

Sheet 1 of 1

Sheet 1 of 1


PlenariesF3 Changing places

Word game

1 Rearrange the letters to find the correct words.

ICDANTSPEMLE happens when metals react with metal salts.

MESNMIUAG is a metal that can displace iron but not calcium.

OLGD is a metal that cannot displace any other metal.

INCZ + iron UHELTASP → INCZ UHELTASP + iron

2 Make up some other clues and see if your friends can workthem out.




F4 PlenariesWho’s top of the league?

Review learning� Class brainstorming to make a list of key facts about

metal reactivity on the board.

� Pupils should consider that more reactive metals reactfaster with oxygen, water and acids, produce moreenergy when they react, and can displace less reactivemetals from their salts.

� Pupils can record the list to act as ‘Key facts’ for revision.

Share responses� Pupils combine into larger groups to compare their

responses to questions from Activity F4a.

� A spokesperson from each group feeds back issues forwhole-class discussion in a short plenary.

Group feedback� Pupils work in groups on a single metal, e.g. sodium,

potassium, calcium, magnesium, zinc, iron, lead, copper,gold.

� Ask each group to record key information from theirnotes about their metal on a piece of A4 card. Write theinformation they need to include on the board.

� Pupils stick their cards in order of reactivity in a list onthe wall.

Word game� Pupils choose two cards, one from each pile, and predict

whether or not a reaction will happen. Their partnerdecides whether or not they are right.

Looking ahead� Write the reactivity series on the board: sodium,

potassium, calcium, magnesium, zinc, iron, lead, copper,gold.

� Ask pupils to make predictions about which metal wouldbe best suited to different uses and explain why.

� Emphasise the importance of understanding metalreactivity when engineers, designers and scientists selectmetals for use.

Key informationName of metal, symbol.How quickly does it react with oxygen?water? acid?

EquipmentA4 coloured paper or card; marker pens;Blu-tack

➔ Pupil sheet

➔ Teacher sheet


Review learning

The class produces a list ofkey facts about metalreactivity.

Sharing responses

Pupils compare theoutcomes of Activity F4a.

Group feedback

Group work to makereactivity series display.

Looking ahead

Pupils discuss how to choose the right metal for the job.


Word game

Play 'react or not' wordgame.

Word game

Cut out the cards. Put all the number 1 cards face down in one pile, and all the number2 cards face down in another pile.

Your partner holds the answer table so that you cannot see it.

Take one card from each pile and decide if the two substances on the cards will reactwhen they are mixed together. See how many you get right, then swap.



1 gold

1 copper

1 iron

1zinc

1 magnesium

1 sodium

1 calcium

1 lead

2 hydrochloric

acid

2 oxygen

2 water

2 zinc sulphate

solution

2 copper sulphate

solution

2 sodium sulphate

solution

2 sulphuric

acid

2 iron sulphate

solution

Metal

sodium

calcium

magnesium

zinc

iron

lead

copper

gold

Oxygen

all thesemetals reactwith oxygen

does not react

Water

these metalsreact quickly

these metals react slowly

do not react

Acid

these metalsreact quickly

these metalsreact slowly

do not react

Metals higher in thetable will react withthese compounds

sodium sulphate

zinc sulphate

iron sulphate

copper sulphate

Answer table



Looking aheadTeacher sheetSamples of questions to use.

1 Which metal would be good to use for fillings in teeth? [Gold because it isunreactive, non-toxic, hard.]

2 Which metals are useful to make fireworks? [Calcium and magnesium,ignite to give out lots of energy/ very reactive.]

3 Which metals are useful in rocket fuels? [Sodium, one of the most reactivemetals, gives out most energy when it burns.]

4 Which metals are useful for large-scale use for water pipes and machinery?[Copper and iron, balance between relatively less reactive/non toxic andavailable in large quantities. Make the point that cost plays a large parthere.]

5 Which metal is used for drinks cans? [Aluminium, has unreactive oxidecoating and so is non-toxic, light, does not corrode.]

6 Which metal, other than gold and silver, is used for expensive jewellery?[Platinum is very unreactive and has similar properties to gold.]

Pupils should realise that other properties, e.g. toxicity, density, electricalconductivity etc., are equally as important as reactivity when deciding how touse metals.




F5 PlenariesReactivity in action

Review learning� Ask pupils to suggest names of metals and how they are

used. Write notes on the board.

� Ask the whole group to suggest which properties areimportant for each use, e.g. copper – electrical wiring –good electrical conductivity etc.

� Encourage pupils to focus on which properties are mostimportant and which are of lesser importance for eachmetal use.

Share responses� Each group makes a two-minute presentation to the rest

of the class to show the outcomes of their research fromActivity F5a.

Group feedback� Pupils mix groups (i.e. combine with pupils from

different working groups) to discuss how they wentabout their research for Activity F5a.

� Pupils devise a bulleted list of ‘Guidelines for carryingout research’.

� A spokesperson from each group feeds back to thewhole class.

Word game� Pupils carry out the matching exercise about metals and

their uses.

Looking back� Pupils revise and consolidate knowledge for the unit.

They can use the Unit map, Pupil checklist or the Testyourself questions.

➔ Pupil sheet

Answers1 copper2 steel3 aluminium, iron oxide4 iron5 lead

➔ Unit map

➔ Pupil checklist

➔ Test yourself


Review learning

Brainstorm of how metalsare used.

Sharing responses

Presentations of outcomesof Activity F5a.

Group feedback

Groups combine to discusshow they carried out theirresearch in Activity F5a.

Word game

Pupils match metals to theiruses.

Looking back

Pupils revise andconsolidate knowledge fromthe unit.


F5 PlenariesReactivity in action

Word game

Draw lines to match the substances in the boxes to the correct descriptions.

Descriptions Substances


1 This metal does not react withwater. It is used in water tanks.

steel

iron

lead

aluminium

iron oxide

copper

2 This substance is a mixture of ironwith other elements.

3 These two substances are used toweld railway lines together.

4 This metal is the most widely usedmetal in the world.

5 This metal is a poisonous metal andis used to make roofing.



F6 PlenariesVariables together – Think about

Group feedback• Ask pupils to use the outcomes of the lesson activities to

make a list of what variables affect rusting. A summary offindings can be made on the board. Identify the twomain variables that are needed for iron to rust (air andwater) and make sure it is clear that both are needed.Discuss how other variables (e.g. salt) can also interact toaffect the rate of rusting.

• Lead a whole-class discussion to relate the list of variables to the methods of rust prevention used on cars and bikes.Focus on how many techniques rely on making a barrierto water and air. Discuss why different techniques areused in different areas, e.g. paint on bodywork and oil onengine parts.

Bridging to other topics• Highlight how two key variables interact to cause rusting,

i.e. air and water. Other variables, such as salt, can affectthe rate of rusting.

• Link this idea to other examples, such as:

1 Yeast needs sugar and water to start working. Othervariables, such as temperature, also affect the rate atwhich it works.

2 Combustion needs an air supply and heat to start thereaction.

3 In industry, engineers often have to make decisions tocontrol several variables that interact to get reactions towork as cheaply and quickly as possible. For example, inmaking ammonia for fertilisers, the temperature andpressure both affect how much ammonia is made.Engineers ‘juggle’ the two variables because it uses a lotof fuel and is very expensive to heat up huge amounts ofchemicals or to keep them under very high pressure.


Group feedback

Groups feed back to the whole group onthe outcomes of their investigations

Bridging to other topics

Focus on variables that interact in rustingand in other examples in science.


F1 SpecialsLosing that shine

1 Write true or false for each sentence.

a Gold doesn’t lose its shine. It is very reactive.

b Iron rusts. Iron is more reactive than gold.

c Paint stops iron rusting.

2 Complete these sentences using the words below.


energyreactive oxidesoxygen

a When metals burn in air, they react with gas.

b Metals form compounds called metal when they react with oxygen gas.

c The more a metal is, the faster it reacts.

d The more reactive a metal is, the more it releases when it reacts.

3 a Cut out the jigsaw pieces. Then match them up to make word equations for metals reacting with oxygen. When you are sure, stick them down.

b For each word equation, colour the reactants in red and the product in blue.

i tin + oxygen

ii potassium + oxygen

iii zinc + oxygen

iv iron + oxygen

→ iron oxide

→ tin oxide

→ copper oxide

→ potassium oxide

v copper + oxygen → zinc oxide

F-Specials.qxd 12-May-04 4:00 PM Page 1

F2 SpecialsCorrosive liquids

1 Use these words to fill in the gaps.


metalshydrogen strongercorrosive

batteriessalt hydroxidecorrode

a The acid used in car is very strong and is

. This means it will many metals.

When an acid reacts with a metal, gas and a

are made.

b Some react with water. A metal and hydrogen gas are made.

c Metals have a reaction with acids than with water.

2 Cut out the jigsaw pieces, then match them up to make word equations for metals reacting with acids and water. When you are sure, stick them down.

i zinc +hydrochloric

→acid

ii iron +sulphuric

→acid

iii potassium + water →

iv sodium + water →

potassium + hydrogenhydroxide

magnesium + hydrogenchloride

zinc + hydrogenchloride

sodium + hydrogenhydroxide

v magnesium +hydrochloric

→acidiron

+ hydrogensulphate


F2 SpecialsCorrosive liquids (continued)


a Very unreactive metals like copper react with water.

b Metals react with water to make a metal hydroxide and hydrogen

gas.

c It would be safe to add sodium, a very reactive metal, to acid.

4 Look at these test tubes. Each test tube has some hydrochloric acid in it and a metal.

a Which metal is the most reactive?

b Which metal is the least reactive?

c Put the metals into order of reactivity, most reactive first.

most reactive least reactive

d When metals react with acids, heat is given out and the temperature rises.

i Which metal will have the highest temperature rise?

ii Which metal will have the lowest temperature rise?


iron zinc copper magnesium


F3 SpecialsChanging places

1 This diagram shows lead ‘winning’ nitrate from silver.

a This type of reaction is called:

displacement

neutralisation burning

b Use the diagram to help you complete this word equation:

lead + silver nitrate → +

c This reaction works because lead is:

more reactive than silver

as reactive as silver less reactive than silver

2 Look at this cartoon.

a Which metal is the most reactive,

iron or zinc?

b Complete this word equation forthe reaction.

zinc + iron → zinc +


a Less reactive metals push more reactive metals out of their

compounds.

b A displacement reaction happens when a more reactive metal

pushes a less reactive metal out of its compound.

c A lot of energy can be released during displacement reactions.

d Displacement reactions can be used to stop iron rusting.


lead

silver nitratesolution

lead nitratesolution

crystals of silver

Tick thecorrectanswer.



F4 SpecialsWho’s top of the league?

1 Use these words to fill in the gaps.


reactivityleast reactions most series

a The is a list of metals.

It has the reactive at the top. The

reactive metal is at the bottom.

b You need to look at chemical to put

metals in order of their reactivity.

2 Look at these beakers. Each beaker contains water and a different metal.

a Which metal reacted the fastest? How can you tell?

b Which metal reacted the least? How can you tell?

c Put the metals in order of their reactivity, most reactive first.


calcium magnesium zinc lithium


F4 SpecialsWho’s top of the league? (continued)

3 Sanjay did some displacement experiments with metals and solutions.These are the results of his experiments.

a Which metal reacted the most?

b Which metal reacted the least?

c Write down the metals in order of their reactivity.



Cobalt reacted with

lead solution.

Cobalt didn’t reactwith zinc solution.

Lead did not react with any of the solutions.

Zinc reacted with cobalt solution

and with lead solution.


F5 SpecialsReactivity in action

1 A mixture of aluminium powder and iron oxide powder can be used tofix cracked railway track. This cartoon shows how.

a The reactants are and .

b The products are hot, liquid and white

.

c The metal has pushed the metal out

of its compound.

d This kind of reaction is called:

replacement

placement

displacement


1 2

3 4

A mixture of aluminium andiron oxide is put in thehopper.

Liquid iron is poured into the crack.REACTION!A lot of heat energy is made!

It needs some heatenergy to kick-start thereaction.



F5 SpecialsReactivity in action (continued)

2 Use some of these words to fill the gaps.

a Reactive metals join in their compounds. It is

to break them up and get the metal.

b It is to break up less reactive metal compounds and

get the metal back.


a Gold and silver stay shiny because they are very reactive.

b Copper roofs last longer than iron roofs. This is because copper is

less reactive than iron.

c Rocks that contain a metal oxide are called ores.

d Titanium is used to make hip joints because it is unreactive.


compoundseasy hard tightly elements


1 Natalie set up anexperiment to find outwhat makes iron rust.Here is her drawing ofher experiment.

Fill in this table using ticks(�) and crosses (✘).

2 Suma’s car has been scratched. The ironunder the scratch has gone rusty.

Use some of these words to fill in the gaps.

a Which two chemicals are needed for iron to rust?

For iron to rust and are needed.

b Explain to Suma why paint stops iron from rusting.

It stops and getting to the iron.

c Suma was surprised to learn that old cars rust less in hot, drydeserts than they do in Britain. Explain to Suma why this is.

This is because

F6 SpecialsVariables together


oxygenwater

no oxygenwater

oxygenno water

1 2

oil

3

silica gel

cotton wool

nail

nailrustynail

Test tube Oxygen? Water? Rust?

1

2

3

wateroxygen acid

wax paint carbon dioxide


F Specials answersPatterns of reactivity

F1 Losing that shine1 a false

b truec true

2 a oxygenb oxidesc reactived energy

3 a i tin + oxygen → tin oxideii potassium + oxygen → potassium oxide

iii zinc + oxygen → zinc oxideiv copper + oxygen → copper oxide

b Reactants coloured red – metals and oxygen.Products coloured blue – metal oxides.

F2 Corrosive liquids1 a batteries, corrosive, corrode, hydrogen, salt

b metals, hydroxidec stronger

2 i zinc + hydrochloric acid → zinc chloride +hydrogen

ii iron + sulphuric acid → iron sulphate +hydrogen

iii potassium + water → potassium hydroxide +hydrogen

iv sodium + water → sodium hydroxide +hydrogen

v magnesium + hydrochloric acid →magnesium chloride + hydrogen

3 a falseb truec false

4 a magnesiumb copperc magnesium, zinc, iron, copperd i magnesium

ii iron (not copper as copper doesn’t react).

F3 Changing places1 a displacement

b silver, lead nitratec more reactive than silver

2 a zincb zinc + iron oxide → zinc oxide + iron

3 a falseb truec trued true

F4 Who’s top of the league?1 a reactivity series, most, least

b reactions2 a lithium, most bubbles

b zinc, no bubblesc lithium, calcium, magnesium, zinc

3 a zincb leadc zinc, cobalt, lead

F5 Reactivity in action1 a aluminium, iron oxide

b iron, aluminium oxidec aluminium, irond displacement

2 a tightly, hardb easy

3 a falseb truec trued true

F6 Variables together1

2 a oxygen, waterb oxygen, waterc There is no water.


Test tube Oxygen? Water? Rust?

1 ✓ ✓ ✓

2 ✗ ✓ ✗

3 ✓ ✗ ✗

Spe Answers.qxd 6/23/2004 9:19 AM Page 6

F1 HomeworkLosing that shine

HELP

1 Read the information below.

a Write down two things that tell Laura a chemical reaction has takenplace.

b Which element, other than magnesium, takes part in the burningreaction?

c What is the name of the white powder left at the end?

d Write a word equation for the reaction that happens when Lauraburns magnesium.

e Laura also tried to burn some silver in the same Bunsen flame. It didnot burn. What does that tell Laura about the reactivity of silver,compared with magnesium?

f Suggest one other metal that would burn even more fiercely thanmagnesium.

CORE

2 Gold is found in rocks as a pure metal, which means that it is notcombined with any other element. Iron can be found in the mineralhaematite, which is a form of iron oxide. It is not found as pure iron.

a i What does the information tell you about how gold and ironreact with oxygen?

ii Why is gold used more than iron in jewellery?

iii Which of the two metals is the more reactive?

b Both iron and sodium react with oxygen. Sodium releases muchmore energy, when it reacts, than does iron. Which of the two isthe more reactive?

c Silver jewellery tarnishes in air but gold does not. What does thistell you about the reactivity of silver?

d Write a word equation for the reaction when iron forms haematitein the earth. You should use the chemical names, not the names ofthe minerals, in your equation.


Laura heats up some magnesium in a Bunsen flame. The shiny grey metalcatches fire and burns with a brilliant, white flame. When it has all burned,Laura is left with a white powder.

F-Homework.qxd 11-May-04 8:16 PM Page 1

F1 HomeworkLosing that shine (continued)

e Copy and complete the following sentences:

i Sodium is kept under oil in a tightly sealed container because

.

ii Platinum used for jewellery does not tarnish because

.

EXTENSION

3 Mrs Archer showed her class some magnesium powder. She sprinkledit into a Bunsen flame to show them how it burned. A spark from theburning powder fell into the stock bottle containing the magnesiumpowder. The whole bottleful caught fire. The teacher poured some waterover the fire. It did not go out, it exploded. The whole class werecovered with a white powder. Miss Chaudry knew what to do. Shecovered the burning beaker with sand. The fire went out but a largehole had been burned in the top of the workbench.

a What mistake did Mrs Archer make during the experiment?

b What does the story tell you about the amount of energy transferredwhen magnesium burns?

c i If the teacher had been demonstrating the burning of powderediron instead, how would the outcome have probably beendifferent?

ii Why would it have been different?

d Why did the water cause an explosion? (Hint: think about theamount of heat energy in the burning magnesium.)

e Why did the flames go out when Miss Chaudry covered the burningmagnesium powder with sand?

4 Look at the two equations about burning, written below.

zinc + oxygen → zinc oxide

and

sodium + oxygen → sodium oxide

a What type of reaction is shown by both equations?

b Luke did both reactions. What was probably the most obviousindication that a chemical change had happened in his experiments?



F2 HomeworkCorrosive liquids

HELP

1 Match the sentence beginnings with the endings to make sentencesabout corrosive liquids. Write out each sentence.

2 a Samantha drops a piece of sodium into a bowl of water. Writedown three things she would see.

b Copy and complete the following word equation:

magnesium + sulphuric acid → + hydrogen

CORE

3 Jonathan sets up the test tubes shown below. There is dilute acid ineach tube. He adds lots of the named metal to each tube.


Beginnings Endings

A When potassium reacts with water 1 calcium chloride and hydrogen are formed.

B When calcium reacts with hydrochloric 2 acids are corrosive.acid

C It is dangerous to react potassium with 3 it forms hydrogen gas, which catches acid because fire.

D Acids can be used to mark decorations 4 acids give stronger reactions with metals onto glass because than water.

addcalcium

A

addmagnesium

B

addmagnesium

C

addmagnesium

D

addgold

E

10 cm3 10 cm3

20 cm3

10 cm3

5 cm3


F2 HomeworkCorrosive liquids (continued)

a i In which tube will there be no reaction?

ii Explain your answer.

b i In which tubes will the volume of hydrogen produced be the same?

ii Why will it be the same?

c In which tube will the greatest volume of hydrogen be given off?

d i Which tube will have the metal bubbling fastest?

ii Why will the metal in this tube bubble faster than the others?

e What would you need to change, in tube D, for it to give the same volume ofhydrogen as tube A?

f All the tubes contain hydrochloric acid. Write a word equation to represent thereaction that is happening in tube C.

EXTENSION

4 The following list contains some metals in decreasing order of reactivity, with themost reactive on the left.

a i Which metal, other than potassium, is likely to react with cold water?

ii Write a word equation to represent the reaction between potassium and water.

The symbol equation for the reaction between potassium and water is givenbelow.

2K + 2H2O → 2KOH + H2

iii How many atoms are there on the left-hand side of the equation?

iv How many atoms are there on the right-hand side of the equation?

b Look back at the diagrams for question 3. All the tubes contain the same acidfrom the same bottle. Sanjay collected the hydrogen from each of the tubeswhere there was a reaction. He collected 30 cm3 of gas from tube B.

i What volume of gas did he collect from tube A?

ii What volume of gas did he collect from tube D?

ii It took Sanjay 2 minutes to collect the gas in tube A. How would the timetaken to collect the gas in tube B compare with the time taken in tube A?


potassium sodium magnesium zinc iron copper gold


F3 HomeworkChanging places

HELP

1 The first list below shows three metals. The most reactive metal is atthe top and the least reactive metal is at the bottom. The second listshows some displacement reactions.

a Match each metal in the first list to a correct statement about it fromthe second list. You can use each metal once, more than once or not at all.

b Explain why magnesium would displace all three of the metals in the list of metals from their solutions.

2 Powdered magnesium reacts with lead oxide.

a Copy and complete the word equation shown below.

magnesium + lead oxide + → +

b This reaction gets very hot. Copy and complete the sentence below:

The reaction between magnesium and lead oxide gets very hotbecause … .

CORE

3 Dave’s dustbin is made from galvanised iron. This means that it is madefrom iron that has been coated with a thin layer of zinc.

a Why is Dave’s dustbin unlikely to go rusty, even if it is scratchedand some of the iron is exposed to air and water?

b Write a word equation to represent what would happen to Dave’sbin if it was scratched and attacked by damp air. (Hint: Rememberwhy zinc blocks are attached to ships.)


List ofmetals

zinc

iron

copper

List of displacement reactions

A This metal displaces copper from coppersulphate solution.

B This metal displaces iron from iron chloridesolution.

C This metal does not displace iron from ironsulphate solution.

D This metal displaces the other two in the listfrom their solutions.


F3 HomeworkChanging places (continued)

c Explain why coating the bin with a thin layer of copper would notbe successful, if the bin was scratched?

d i Copper sulphate solution is blue. Iron sulphate solution is palegreen. Copper metal is pinkish-brown. Iron metal is shiny silver.

Describe what you would see happening, to the iron and to thesolution, if a lot of powdered iron was added to a small amount ofcopper sulphate solution.

ii Explain why these changes would happen.

EXTENSION

4 Sand contains silicon dioxide in a fairly pure form. The silicon neededfor computer chips is made by reacting silicon dioxide with aluminium.

a i Which is more reactive, the silicon or the aluminium?


b Explain why the temperature of the silicon that is made in thisreaction is more than 500°C.

c Suggest a reason why the fairly high cost of the silicon made bythis reaction is not related to the cost of the silicon dioxide.

5 A similar reaction is used, in a blast furnace, to extract iron from ironore. One type of iron ore is haematite, which contains iron oxide. It isreacted with carbon. One of the products of the reaction turnslimewater milky.

a Which is the more reactive, the iron or the carbon?

b The iron is produced as a liquid but its melting point is 1539°C.What does this tell you about the energy changes during thereaction?

c What type of reaction is taking place in the blast furnace toextract the iron from the iron ore?

d What is the gas that is also produced?



F4 HomeworkWho’s top of the league?

HELP

1 The list below shows some elements in order of their reactivity. Themost reactive is on the left.

Choose metals from the list to answer the following questions.

a This metal will displace all the other metals from solutions of their salts.

b This metal cannot be displaced from solution by any of the others.

c This metal will only displace gold from a solution.

d This metal displaces silver but is displaced from its solution by iron.

2 a Copy and complete the following sentences:

i Gold is used for jewellery because … .

ii Copper can be used for making water pipes because … .

b Copper sulphate solution is blue. Zinc sulphate solution is colourless.Sarah adds a lot of zinc powder to some copper sulphate solution. Howdoes she know that a displacement reaction has happened?

CORE

3 Read the information about some chemical reactions and use it toanswer the questions.

a i Which is the most reactive metal?


b i Which two metals will displace iron from a solution of iron sulphate,without reacting quickly with the water itself?

ii Write a word equation for the reaction between one of thesemetals and iron sulphate.


magnesium iron copper silver gold

Magnesium reacts quickly with dilute acids but not with water. Sodiumreacts with water but rubidium reacts much faster. Gold does not react withwater or acids and it does not tarnish in air. Neither zinc nor iron reactquickly with water but zinc reacts with acids faster than iron. Copper doesnot react with water or acid but it tarnishes in air. So does silver, which isdisplaced from solution by copper.


F4 HomeworkWho’s top of the league? (continued)

c Write down all the metals described in order of their reactivity,starting with the most reactive.

d i Manganese reacts fairly quickly with dilute acids, though notwith water. It will displace zinc from a solution of its salts. Suggestwhere manganese would best fit into the reactivity series you havedrawn up.


EXTENSION

4 Read the information about some chemical reactions and use it to answerthe questions. It is the same as the information given for question 3.

a Write a word equation for the reaction between copper and silvernitrate solution.

b The symbol equation below shows the reaction between magnesiumand hydrochloric acid. What is the total number of atoms shown onboth sides of the equation?

Mg + 2HCl → MgCl2 + H2

c Use the reactivity series below to answer the following questions.The most reactive metal is on the left.

i Write a word equation to show the reaction when powderednickel is heated with platinum oxide.

ii The formula of zinc oxide is ZnO and the formula of copper oxideis CuO. Use these to write a formula equation to represent thereaction between zinc and copper oxide.

iii Describe what you would do to show that nickel really is abovecopper in the reactivity series shown above.


Magnesium reacts quickly with dilute acids but not with water. Sodiumreacts with water but rubidium reacts much faster. Gold does not react withwater or acids and it does not tarnish in air. Neither zinc nor iron reactquickly with water but zinc reacts with acids faster than iron. Copper doesnot react with water or acid but it tarnishes in air. So does silver, which isdisplaced from solution by copper.

zinc nickel copper platinum


F5 HomeworkReactivity in action

HELP

1 The list shows a reactivity series for some metals. The most reactiveis on the left.

Use the metals in the list to answer the following questions:

a i Which of the reactions shown below would actually happen?Write down the letters.

A copper + magnesium oxide → magnesium + copper oxide

B zinc + silver oxide → silver + zinc oxide

C magnesium + copper oxide → copper + magnesium oxide

D aluminium + iron oxide → iron + aluminium oxide

E iron + zinc oxide → zinc + iron oxide

ii Which of the lettered reactions would be useful for mending abroken railway line?

b i Give one property of silver that explains why it is used in earrings.

ii Copy and complete the sentence:

Silver has this property because … .

c i Aluminium oxide is sometimes called a metal ore. What are ores?

ii Suggest one metal, from the reactivity series above, that youcould use to extract magnesium from magnesium oxide.

CORE

2 Information about some metals is given below. Use the informationto answer the questions about the metals.


aluminium magnesium zinc iron copper silver

Metal Information

Copper Fairly unreactive but will dissolve in acidic water.

Lead More reactive than copper and toxic to humans.

Aluminium Quickly forms a protective oxide coating all over its surface.

Platinum Unreactive and silver in colour.

Magnesium Burns fiercely in air.

Iron Reacts with air and water.


F5 HomeworkReactivity in action (continued)

a Metal pencil sharpeners are often made from magnesium becauseit is light but strong. Why is it very dangerous to put them into a flame?

b Explain why aluminium is used for bottle tops, even though it is a reactive metal.

c Why do water companies make sure that tap water is always neutral?

d Why is it necessary to oil a bicycle chain made from steel?

e i Paul’s granny lives in a house with lead water pipes. She saysshe needs to run the tap for a minute before she uses the water fordrinking. Why is this a good idea?

ii What advice would you give to Paul’s granny, so that she wouldnot need to run off water every time she wants a drink?

f i Explain why platinum can be used to make jewellery.

ii Suggest another metal, not in the table, that could be confusedwith platinum used in this way.

EXTENSION

3 a Some metals have been known for thousands of years but othershave only been discovered in the last couple of centuries. Use yourknowledge of the reactivity series to explain the statements below.

i Sodium was discovered in 1807.

ii Gold was one of the earliest metals to be discovered.

iii Copper was known before iron.

iv The Romans used lead to line water tanks.

v Aluminium has only been used on a large scale for about 150 years.

b Carbon can be used to extract copper from copper ore (copper oxide).It is mixed with the ore and heated to start the reaction. Carbon dioxideis also produced.

i What does this suggest about the position of carbon in the reactivity series?

ii Write a word equation to represent the reaction between carbonand copper ore.

iii How many atoms are there on each side of the equation shown below?

C + 2CuO → 2Cu + CO2



F1Homework

mark schemeLosing that shine


HELPQuestion Answer Mark

1 a It burned/gave out heat/gave out light/caught fire. 1It formed a white powder. 1

b Oxygen 1

c Magnesium oxide 1

d Magnesium + oxygen → magnesium oxide 2Award 1 mark for the reactants and 1 mark for the product.

e Silver is less reactive than magnesium. 1

f Any correct choice, e.g. potassium/sodium, etc. 1

Total for Help 8

COREQuestion Answer Mark

2 a i Gold does not react with oxygen. 1Iron reacts with oxygen. 1

ii It keeps its shine for longer/it does not tarnish/corrode. 1

iii Iron 1

b Sodium 1

c It is more reactive than gold. 1

d Iron + oxygen → iron oxide 2Award 1 mark for the reactants and 1 mark for the products.

e i Sodium is kept under oil in a tightly sealed container because this stops itfrom reacting with oxygen in the air. 1Underscore is pupil response. Accept equivalent responses.

ii Platinum used for jewellery does not tarnish because it is unreactive/it doesnot react with oxygen. 1Underscore is pupil response. Accept equivalent responses.

Total for Core 10

EXTENSIONQuestion Answer Mark

3 a She left the lid off the container. 1

b It transfers lots of energy. 1

c i The iron in the bottle might not have caught fire/there might not have been a flying spark. 1Accept other sensible responses.

ii Iron is less reactive than magnesium. 1

d The water boiled instantly making lots of vapour. 1

e The sand prevented oxygen from getting to the fire. 1

4 a Oxidation Accept combustion/burning. 1

b They both produced heat/both burned/both produced a new substance. 1

Total for Extension 8


F2Homework

mark schemeCorrosive liquids



1 Correct sentence matches are: A 3; B 1; C 4; D 2 4

2 a Three from: floats; fizzes/bubbles; dissolves; makes steam not smoke; moves over water surface; becomes a sphere. 3

b Missing substance is magnesium sulphate. 1

Total for Help 8


3 a i Tube E 1

ii Gold is very unreactive/does not react with acids. 1

b i Tubes A and B. Both tubes needed for the mark. 1

ii They both contain the same amount of acid. 1

c Tube C 1

d i Tube A 1

ii Calcium reacts faster/is a more reactive metal than the others. 1

e Add another 5 cm3 of acid/double the volume of acid. 1

f Magnesium + hydrochloric acid → magnesium chloride + hydrogen 2Award 1 mark for the reactants and 1 mark for the products.

Total for Core 10


4 a i Sodium 1

ii Potassium + water → potassium hydroxide + hydrogen 2Award 1 mark for potassium and 1 mark for hydrogen.

iii 8 1

iv 8 1

b i 30 cm3 1

ii 15 cm3 1

iii It would be slower/it would take longer. 1



F3Homework

mark schemeChanging places



1 a Statement matches are: A – zinc or iron 1B – zinc 1C – copper 1D – zinc 1

b It is more reactive than they are. 1

2 a Lead + magnesium oxide 2Products can be written either way round. 1 mark for each product.

b The reaction between magnesium and lead oxide gets very hot because itgives out/produces/releases heat energy. 1Underscore is pupil response.

Total for Help 8


3 a It is protected by the zinc/the zinc will corrode instead of the iron. 1

b Zinc + oxygen → zinc oxide Award 1 mark for each correct substance, if it is 3on the correct side of the arrow.

c Copper is less reactive than iron 1so the iron would rust/corrode instead of the copper. 1

d i The solution would turn from blue to pale green. 1The surface of the iron would change from silver to pinkish brown. 1

ii The iron is more reactive than the copper 1so it has displaced it from the blue solution. 1

Total for Core 10


4 a i The aluminium. 1

ii It displaced the silicon from silicon dioxide. 1

b The reaction gives out heat energy/is exothermic. 1

c Sand is very common/very cheap to buy. 1Accept other equivalent responses.

5 a The carbon. 1

b Energy is given out/released/produced during the reaction. 1

c A displacement reaction. 1

d Carbon dioxide 1



F4Homework

mark schemeWho’s top of the league?



1 a Magnesium 1

b Magnesium 1

c Silver 1

d Copper 1

2 a i Gold is used for jewellery because it does not tarnish/it keeps its shine. 1Underscore is pupil response. Accept equivalent responses.

ii Copper can be used for making water pipes because it does not react with water. 1Underscore is pupil response.

b The solution loses its colour/changes from blue to colourless. First option scores 2both marks. Second option gains one mark for each specified colour.

Total for Help 8


3 a i Rubidium 1

ii It reacts faster than sodium which is the only other metal to react with water. 1

b i Magnesium and zinc. 1

ii Zinc/magnesium + iron sulphate → iron + zinc/magnesium sulphate 2Award 1 mark for reactants and 1 for products.

c Order is:Rubidium, sodium, magnesium, zinc, iron, copper, silver. 2All correct = 2 marks; one error = 1 mark.

d i Between magnesium and zinc. 1

ii It reacts more slowly with acids than magnesium with acids, so is less reactive than magnesium 1but displaces zinc, so is more reactive than zinc. 1

Total for Core 10


4 a Copper + silver nitrate → silver + copper nitrate 1Award mark for correct products.

b 10 1

c i Nickel + platinum oxide → platinum + nickel oxide 1Award mark for correct products.

ii Zn + CuO → Cu + ZnO 21 mark for correct reactants; 1 mark for correct products.

iii Mix some powdered nickel with some copper oxide. 1Heat it using a Bunsen burner. 1Look for evidence of an exothermic reaction/a reaction producing heat. 1Accept equivalent response to third point.



F5Homework

mark schemeReactivity in action



1 a i B, C and D. 3One mark off for each omission.

ii D 1

b i It is shiny/it is unreactive. 1

ii Silver has this property because it does not react quickly with oxygen. 1Accept alternative equivalent responses.

c i Compounds of metals found in rocks. 1Must mention compounds ... in rocks for the mark.

ii Aluminium 1

Total for Help 8


2 a They would burn fiercely. 1

b It has already reacted with oxygen to form a protective coating, 1so does not react further. 1

c So that it does not react with the copper pipes. 1

d Iron reacts with water and oxygen/air. 1

e i Running water off removes the water standing in the lead pipes 1so that the drinking water does not contain lead. 1

ii Have the pipes replaced with copper ones. 1

f i It is shiny and unreactive. Needs both points for the mark. 1

ii Silver/nickel/gold 1

Total for Core 10


3 a i Sodium is a very reactive metal. 1

ii Gold is found unreacted/as the pure element. 1

iii Copper is less reactive than iron. 1

iv Lead can be easily obtained from its ore/is low in the reactivity series. 1

v Aluminium is a reactive metal/is high in the reactivity series. 1

b i Carbon is above iron in the reactivity series. 1

ii Carbon + copper oxide → copper + carbon dioxide 1

iii 5 on each side. Accept 5. 1



F Test yourselfPatterns of reactivity

1 a When a metal tarnishes, it reacts with a gas in the air.

i What is the name of this gas?

ii What sort of metal compound is formed in this reaction?

b When iron tarnishes in air, it also reacts with water and forms a brown solid on the surface of the metal. What is the name of this brown solid?

c Name a metal that does not tarnish when exposed to air.

2 Small pieces of three very reactive metals are dropped into water.

The water is then tested with Universal Indicator.

The table shows the results from this experiment.

a Name (a) the gas and (b) the metal compound produced in these reactions.

a b

b Use information in the table to write these alkali metals in order of reactivity, startingwith the most reactive.

c What does the Universal Indicator colour show you about the water?

d Complete this word equation for the reaction of sodium with water.

sodium + water → +


Very reactive Observation when metal is Result of test with metal dropped into water Universal Indicator

lithium steady bubbling, metal moves around purplesurface of water

potassium violent bubbling, gas ignites, metal purpleshoots around surface

sodium fast bubbling, metal moves quickly on purplesurface

Test-Qust.qxd 6/25/2004 10:32 AM Page 17

F Test yourselfPatterns of reactivity (continued)

3 a This table shows how some metals react with dilute hydrochloric acid.

Use the information in the table to write the four metals in order of reactivity, starting with the most reactive.

b Describe a test to prove that hydrogen is the gas given off.

4 Small pieces of zinc are added to solutions containing the nitrates of four other metals. The results of this displacement experiment are shown in the table.

a i From the results in the table, which metal is more reactive than zinc?

ii Explain how the results show this.

b Complete this word equation for the reaction of zinc with iron nitrate.

zinc + iron nitrate → +


Metal Observation in cold hydrochloric acid

copper no reaction

iron a few bubbles

magnesium vigorous bubbling

zinc steady bubbling

Metal nitrate in solution Observation of piece of zinc

copper turns brown

iron turns black

magnesium no change

silver turns black


F Test yourselfPatterns of reactivity (continued)

5 Complete the following passage by crossing out the words that are wrong.

The reactivity sequence/series is a list of metals with the most/leastreactive at the top and the most/least reactive at the bottom. Silver corrodes easily so it is above/below gold.

6 In the Thermit reaction, aluminium powder is mixed with iron oxide. The reaction is violent, giving off sparks and clouds of smoke. Molten iron is produced.

a What does this reaction tell you about the positions of aluminium and iron in the reactivity series?

b Write a word equation for the reaction.

c Which two observations tell you that this reaction releases a lot of energy?

d Give one use of the Thermit reaction.

7 In a piece of gold ore, small pieces of the yellow metal can be seen. In a piece of iron ore, no iron metal can be seen. The iron ore contains iron oxide.

Explain this difference.

8 Use ideas about the properties of metals to explain each of the following statements.

a Copper is used instead of iron to make water pipes.

b Gold is used instead of calcium to make jewellery.

c Aluminium is used instead of iron to make aeroplane bodies.



FTest yourself

AnswersPatterns of reactivity

1 a When a metal tarnishes, it reacts with a gas in the air.

i What is the name of this gas?

ii What sort of metal compound is formed in this reaction?

b When iron tarnishes in air, it also reacts with water and forms a brown solid on the surface of the metal. What is the name of this brown solid?

c Name a metal that does not tarnish when exposed to air.

2 Small pieces of three very reactive metals are dropped into water. The water is then tested with Universal Indicator.

The table shows the results from this experiment.

a Name (a) the gas and (b) the metal compound produced in these reactions.

a b

b Use information in the table to write these alkali metals in order of reactivity, startingwith the most reactive.

c What does the Universal Indicator colour show you about the water?

d Complete this word equation for the reaction of sodium with water.

sodium + water → + hydroxide

hydrogensodium

It is alkaline/contains a metal hydroxide.

lithiumsodiumpotassium

metal hydroxidehydrogen

platinum, gold or silver

rust

oxide

oxygen


Very reactive Observation when metal is Result of test with metal dropped into water Universal Indicator

lithium steady bubbling, metal moves around purplesurface of water

potassium violent bubbling, gas ignites, metal purpleshoots around surface

sodium fast bubbling, metal moves quickly on purplesurface

Test-Ans.qxd 16-Jun-04 2:55 PM Page 17

FTest yourself

AnswersPatterns of reactivity (continued)

3 a This table shows how some metals react with dilute hydrochloric acid.

Use the information in the table to write the four metals in order of reactivity, starting with the most reactive.

b Describe a test to prove that hydrogen is the gas given off.

4 Small pieces of zinc are added to solutions containing the nitrates of four other metals. The results of this displacement experiment are shown in the table.

a i From the results in the table, which metal is more reactive than zinc?

ii Explain how the results show this.

b Complete this word equation for the reaction of zinc with iron nitrate.

zinc + iron nitrate → + nitratezinciron

reactive than magnesium.

Zinc did not displace magnesium from a solution of its salt, so zinc is less

magnesium

Hydrogen explodes with a squeaky pop.

Put a lighted splint at the mouth of a test tube of the gas.

copperironzincmagnesium


Metal Observation in cold hydrochloric acid

copper no reaction

iron a few bubbles

magnesium vigorous bubbling

zinc steady bubbling

Metal nitrate in solution Observation of piece of zinc

copper turns brown

iron turns black

magnesium no change

silver turns black


FTest yourself

AnswersPatterns of reactivity (continued)

5 Complete the following passage by crossing out the words that are wrong.

The reactivity sequence/series is a list of metals with the most/leastreactive at the top and the most/least reactive at the bottom. Silver corrodes easily so it is above/below gold.

6 In the Thermit reaction, aluminium powder is mixed with iron oxide. The reaction is violent, giving off sparks and clouds of smoke. Molten iron is produced.

a What does this reaction tell you about the positions of aluminium and iron in the reactivity series?

b Write a word equation for the reaction.

c Which two observations tell you that this reaction releases a lot of energy?

d Give one use of the Thermit reaction.

7 In a piece of gold ore, small pieces of the yellow metal can be seen. In a piece of iron ore, no iron metal can be seen. The iron ore contains iron oxide.

Explain this difference.

8 Use ideas about the properties of metals to explain each of the following statements.

a Copper is used instead of iron to make water pipes.

b Gold is used instead of calcium to make jewellery.

c Aluminium is used instead of iron to make aeroplane bodies.

Iron is heavier and would rust.

Aluminium is less dense than iron and does not corrode.

Calcium is much more reactive and would harm skin.

Gold does not react with acid in sweat or with air.

Iron reacts with water and air to form rust.

Copper does not react with water and air.

Iron is reactive and has reacted with oxygen to form iron oxide.

Gold is unreactive and so has not joined to another element to form a compound.

welding railway lines

Any two of: sparks given off; smoke given off; molten iron produced.

aluminium + iron oxide → iron + aluminium oxide

Aluminium is above iron.



FEnd of unit test

GreenPatterns of reactivity

1 Look at this reactivity series.

a Which metal is more reactive than lithium? 1 mark

b Is copper less reactive than magnesium? 1 mark

2 a The table below shows what is seen when some metals are addedto dilute sulphuric acid. Use the observations in the table belowto rank the four metals in order of reactivity, from most reactiveto least reactive. 3 marks

b Copy and complete this word equation for the reaction of zincwith sulphuric acid. 2 marks

zinc + acid → zinc + hydrogen

3 a When iron is added to lead sulphate a reaction takes place. Is ironmore or less reactive than lead? 1 mark

b When copper is added to lead sulphate no reaction takes place.Is copper more or less reactive than lead? 1 mark

c Copy and complete this word equation for the reaction wheniron is added to lead nitrate solution. 1 mark

iron + lead nitrate →→ + iron nitrate


potassium more reactive

lithium

magnesium

copper

silver less reactive

Metals Observations in dilute sulphuric acid

copper no reaction

zinc bubbles given off steadily

calcium bubbles given off very quickly

lead bubbles given off very slowly

D-F-EUTest.qxd 18-Jun-04 1:44 PM Page 15

FEnd of unit test

GreenPatterns of reactivity (continued)

4 Small pieces of the metals lithium, potassium and sodium were cut from larger pieces. The time taken for the exposed shiny surfaceof each metal to go dull was noted.

Each of the small pieces of metal was placed in a trough of water,and the reaction observed.

Results of this experiment are shown in the table.

a From the information in the table, choose two things that show that potassium is the most reactive of the three metals. 2 marks

b Use the information in the table to write the three metals in orderof reactivity, starting with the most reactive. 1 mark

c What is the name of the compound formed when the shiny surface of potassium goes dull as it is exposed to the air? 1 mark

d Copy and complete this word equation for the reaction oflithium with water. 2 marks

lithium + water →→ lithium +

5 Use ideas about reactivity to explain the following facts.

a In samples of their ores, gold is found as gold metal but aluminiumis found as aluminium oxide. 2 marks

b Copper is used to make water pipes but iron is not. 2 marks


Metal Time taken to go dull Observations of reaction (seconds) in water

lithium 37 steady bubbling, metal movesslowly over surface of water

potassium 4 violent bubbling, gas burns, metal shoots around on surface of water

sodium 18 fast bubbling, metal moves quicklyover surface of water


FEnd of unit test

GreenPatterns of reactivity (continued)

6 David is investigating the corrosion of iron.He predicts that oxygen is needed foriron to rust.

The diagram shows the two test tubeshe has set up.

Boiling the tap water removes any gasesthat are dissolved in the water.

a What factor is being controlled inthis experiment? Choose one from:water, oxygen, temperature,mass of the nail. 1 mark

David’s results after three days areshown in this table:

Asif says that this does not prove that Davidwas right. He says water is needed to makeiron rust. David and Asif do the experiment again with fresh test tubes A and B, and anew test tube C.

These are the results of the second experimentafter three days:

b i How many factors are being controlled in the second experiment? 1 markii Suggest why Asif put a rubber bung into the top of test tube C. 1 mark

Their conclusion is that both oxygen and water are needed for iron to rust.

c i Which tubes support this conclusion for oxygen? 1 markii Which tubes support this conclusion for water? 1 mark


Test tube A: ironnail in distilled water

Test tube B: ironnail in boiled tap water

Test tube Result

A slight rust on nail

B no rust on nail

Test tube Result


B no rust on nail

C no rust on nailTest tube C: iron

nail and a chemicalto absorb water


FEnd of unit test

RedPatterns of reactivity

1 Small pieces of the metals lithium, potassium and sodium were cut from larger pieces. The time taken for the exposed shiny surface ofeach metal to go dull was noted.

Each piece of metal was placed in a trough of water, and the reaction observed.

Results of this experiment are shown in the table.

a From the information in the table, choose two things that showthat potassium is the most reactive of the three metals. 2 marks

b Use the information in the table to write the three metals in order of reactivity, starting with the most reactive. 1 mark

c What is the name of the compound formed when the shinysurface of potassium goes dull as it is exposed to the air? 1 mark

b Copy and complete this word equation for the reaction oflithium with water. 2 marks

lithium + water → lithium +

2 Use ideas about reactivity to explainthe following facts.

a In samples of their ores, goldis found as gold metal butaluminium is found asaluminium oxide. 2 marks

b Copper is used to makewater pipes but iron is not. 2 marks

3 Part of the reactivity series ofmetals is shown here.

Carbon is also included.


sodium more reactive

calcium

carbon

zinc

iron

lead

gold less reactive

Metal Time taken to go dull Observations of reaction (seconds) in water

lithium 37 steady bubbling, metal movesslowly over surface of water

potassium 4 violent bubbling, gas burns, metal shoots around on surface of water

sodium 18 fast bubbling, metal moves quicklyover surface of water


FEnd of unit test

RedPatterns of reactivity (continued)

Use this list to help you answer the following questions.

a The table gives observations of some reactions of copper, iron,lead and zinc with hot and cold hydrochloric acid.

A piece of tin was tested with cold and then hot hydrochloric acid.In the cold acid no reaction was seen, but in the hot acid a slowbubbling was observed

i Where should tin be placed in the reactivity series? 1 markii Write a word equation for the reaction of tin with dilute

hydrochloric acid. 2 marks

b Gold was discovered thousands of years ago, but metals likesodium were not discovered until much later. Explain this difference. 2 marks

c Iron is extracted from an ore containing iron oxide by heatingit with carbon. Explain why this is. 2 marks

4 A piece of iron is placed in a solution of lead nitrate, Pb(NO3)2, and left for a few minutes. Like lead, one iron atom combines with two nitrates.

a What would you see during this experiment? 1 mark

b The symbol equation for the reaction between iron and lead nitrate is:

Fe + Pb(NO3)2 → Pb + Fe(NO3)2

Complete both tables to show the number of atoms in each side of the equation. 2 marks


Metal Observations in cold Observations in hot hydrochloric acid hydrochloric acid

copper no reaction no reaction

iron a few bubbles steady bubbling

lead no reaction a few bubbles

zinc steady bubbling vigorous bubbling

Number of atoms

Fe Pb N O

Number of atoms

Fe Pb N O


FEnd of unit test

RedPatterns of reactivity (continued)

5 David is investigating the corrosion of iron. Hepredicts that oxygen is needed for iron to rust.

The diagram shows the two test tubes he hasset up. Boiling the tap water removes anygases that are dissolved in the water.

David’s results after three days are shown inthis table:

Asif says that this does not prove that David was right. He says wateris needed to make iron rust. David and Asif do the experiment againwith fresh test tubes A and B, and a new test tube C.

These are results of the second experiment after three days:

Their conclusion is that both oxygen and water are needed for ironto rust.

a i Which tubes support this conclusion for oxygen? 1 markii Which tubes support this conclusion for water? 1 mark

Asif says that iron rusts more quickly at the seaside. He prepares afourth test tube, test tube D. He carefully weighs the nail beforeputting it into the test tube. After three days, the nail is very rusty.Asif weighs the nail again.

b What should Asif do before weighing the nail again? Give a reason for your answer. 1 mark

c i Compare the mass of the rusty nail with its mass before the experiment. 1 mark

ii Suggest a reason for your answer. 1 mark


Test tube C: ironnail and a chemical

to absorb water

Test tube D: ironnail and salt water

solution

Test tube Result


B no rust on nail

Test tube Result


B no rust on nail

C no rust on nail

Test tube A: ironnail in distilled water

Test tube B: ironnail in boiled tap water



FEnd of unit test

mark schemePatterns of reactivity

Green (NC Tier 3–6)Question Answer Mark Level

1 a Potassium 1 3

b Yes 1 3

2 a Calcium; Zinc; Lead; Copper. Three marks for four correct; two marks for three correct; one mark for two correct. 3 4

b Zinc + sulphuric acid → zinc sulphate + hydrogenL4 mark for sulphuric in correct space, L5 mark for sulphate 1 4in correct space. 1 5

3 a More 1 5

b Less 1 5

c Iron + lead nitrate → lead + iron nitrate One mark for product lead. 1 4

4 a Two from: Goes dull most quickly; Gives off bubbles most quickly; Moves around on surface most quickly; Gas burns. 2 5

b Potassium, sodium, lithium. 1 5

c Potassium oxide. 1 6

d Lithium + water → lithium hydroxide + hydrogen One mark for hydroxide in correct space, one mark for hydrogen in correct space. 2 6

5 a Aluminium is more reactive than gold or gold is less reactive 1 5than aluminium.Aluminium has reacted with oxygen or gold has not reacted 1 6with oxygen.

b Iron is more reactive than copper or copper is less reactive than iron. 1 5Iron would rust or copper does not react with air and water. 1 6

6 a Oxygen/gases from the air. 1 4

b i Two 1 5ii To stop any water vapour from the air outside the test tube from

getting to the nail. 1 5

c i A and B. 1 6ii C and B. 1 6

Scores in the range of: NC Level

4–6 3

7–11 4

12–16 5

17–25 6



FEnd of unit test

mark schemePatterns of reactivity

Red (NC Tier 5–7*)Question Answer Mark Level

1 a Two from: Goes dull most quickly; Gives off bubbles most quickly; Moves around on surface most quickly; Gas burns. 2 5

b Potassium, sodium, lithium. 1 5

c Potassium oxide. 1 6

d Lithium + water → lithium hydroxide + hydrogen One mark for hydroxide in correct space, one mark for hydrogen in correct space. 2 6

2 a Aluminium is more reactive than gold or gold is less reactive than aluminium. 1 5Aluminium has reacted with oxygen or gold has not reacted with oxygen. 1 6

b Iron is more reactive than copper or copper is less reactive than iron. 1 5Iron would rust or copper does not react with air and water. 1 6

3 a i Between iron and lead. 1 6ii Tin + hydrochloric acid → tin chloride + hydrogen

Deduct one mark for each error up to two marks. 2 6

b Gold (in gold ore) does not react to form compounds (but sodium does react). 1 7Gold does not have to be separated from other elements(but sodium does have to be separated). Accept the reverse arguments. 1 7

c Carbon is above iron in the reactivity series. 1 7Carbon displaces iron from the iron oxide. 1 7*

4 a The iron goes black or bubbles appear. 1 7

b Left-hand side: Fe = 1; Pb = 1; N = 2; O = 6. Right-hand side: Fe = 1; Pb = 1; N = 2; O = 6. 2 7*

5 a i A and B. 1 6ii C and B. 1 6

b Dry it carefully, because any water would increase the mass. 1 6

c i The rusty nail would be heavier. 1 7ii Iron has combined with oxygen to make a new compound. 1 7

Scores in the range of: NC Level

5–10 5

11–14 6

15–18 7

19–25 7*


F Pupil checklistPatterns of reactivity


Learning outcomes I can do I can do I need to this very this quite do more well well work on this

I can describe how some metals react with oxygen.

I can describe how some metals react with water and acids.

I can name metals that do not react with oxygen, water or acids.

I can use the reactivity series to predict how a metal will react with oxygen, water or acids.

I can write word equations for the reactions in this unit.

I can describe what happens in metal displacement reactions.

I can work out an order of reactivity of metals using information about displacement.

I can use the reactivity series to make predictions about displacement reactions.

I can name some uses of different metals.

I can explain why different metals are chosen for different jobs.

I can identify when a chemical change has taken place.

I can safely carry out reactions using metals, acids and solutions.

I can discuss how variables interact when iron rusts.

Pupil-Checklist.qxd 17-Jun-04 8:00 PM Page 6

F GlossaryPatterns of reactivity


Word

dependent variable R

displacementreaction

independent variable R

interact

ore

oxide

reactive

reactivity series

unreactive

Definition

A compound formed when a substance burns and joins withoxygen in the air.

An unreactive substance does not take part in chemicalreactions, or does so only slowly.

A reactive substance takes part in chemical reactions, usuallyquickly and releasing lots of energy.

A chemical reaction in which an element is removed from itscompound by a more reactive element.

A list of metals arranged in order of reactivity, with the mostreactive at the top.

A rock containing a metal or a metal compound.

When two or more things have an effect on each other.

A variable (something that can be measured) whose valuedoes not depend on anything else. Usually the x-axis on a graph. R

A variable (something that can be measured) whose valuedepends on that of something else. Usually the y-axis on a graph. R

Glossary.qxd 18-Jun-04 11:33 AM Page 7

F Key wordsPatterns of reactivity


displacement reaction


interact

ore

oxide

reactive

reactivity series

unreactive


displacement reaction


interact

ore

oxide

reactive

reactivity series

unreactive

Sheet 1 of 1

Sheet 1 of 1


Key wordsF Patterns of reactivity


Keywords.qxd 18-Jun-04 11:35 AM Page 6


F Book answersPatterns of reactivity

F1 Losing that shineGreena The air.b Water or moisture.c The layer of paint on the iron keeps the oxygen

in the air from reacting with the iron.d To keep oxygen from reaching and reacting with

the potassium.e A new substance, potassium oxide, is formed.f Zinc oxide.1 Gold stays shiny because it is a very unreactive

metal. Potassium has to be stored away from airbecause it is a very reactive metal.

2 Potassium, zinc, copper, gold.3 a Tin oxide.

b tin + oxygen → tin oxidec Heating potassium in the air is dangerous

because it would burst into flames.Reda Potassium loses its shine when cut in air. The new

substance is the dull coating of potassium oxide.Heat is given off as the oxide coating forms.

b i rustii oxygen

c The mass would have gone up. The copper hadgained oxygen so the mass of the oxide wouldbe greater than the copper at the start.

d i Hydrogen sulphide.ii silver + hydrogen sulphide →

silver sulphide + hydrogeniii Where the air is clean, as in the country, no

silver sulphide is formed.iv Volcanoes and swamps naturally contain

hydrogen sulphide gas.1 Potassium, zinc, iron, copper, gold.2 a tin + oxygen → tin oxide

b Heating potassium in the air is dangerousbecause it would burst into flames.

c It melted. Platinum is an unreactive metaland would not form an oxide. It has amelting point below the temperature of theBunsen flame.

3 The magnesium in the battleship burned in theair giving off heat and magnesium oxide.

F2 Corrosive liquidsGreena magnesium + hydrochloric acid → magnesium

chloride + hydrogenb i magnesium

ii copperc You would have to compare the volumes of gas

collected after the reactions have completelyfinished. The reactions have finished when allof the bubbles have stopped coming off fromthe solutions.

d sodium + water → sodium hydroxide +hydrogen

e Any unreactive metal, such as copper, gold,silver, platinum, mercury, tin, etc.

1 iron + sulphuric acid → iron sulphate + hydrogenmagnesium + sulphuric acid → magnesiumsulphate + hydrogencalcium + hydrochloric acid → calcium chloride +hydrogen

2 a sodiumb i Magnesium and zinc.

ii magnesium3 Potassium reacts violently with water.

Reda The temperature rise will be greatest with the

magnesium, less with zinc and no temperaturerise at all with copper.

b hydrogenc sodium + water → sodium hydroxide +

hydrogen1 a sodium

b magnesium + sulphuric acid → magnesiumsulphate + hydrogen

c i Magnesium and zinc.ii magnesium

2 Potassium reacts violently with water.3 It took 120 seconds or twice as long.

F3 Changing placesGreena Heat was given out by the chemical reaction.b i Iron is more reactive than copper. Iron

replaces the copper and joins with sulphate.The copper was pushed out of its compoundto remain on its own.

ii copper sulphate + iron → iron sulphate +copper

c No. Zinc is more reactive than copper. Thecopper cannot push the zinc back out of thecompound.

d Zinc. Zinc is more reactive than iron. The zincreacts with the oxygen instead of the iron.

1 A more reactive metal can displace a lessreactive metal from its compound.

2 a magnesium + nickel chloride → magnesiumchloride + nickel

b The colour of the solution would graduallychange from green to colourless.

3 a Aluminium is more reactive. Aluminiumdisplaces iron from its compound.

b aluminium + iron oxide → iron + aluminiumoxide

c A lot of heat is given out during the reactionand the iron melts.

Book Answers.qxd 18-Jun-04 12:44 PM Page 15


F Book answersPatterns of reactivity (continued)

Reda Heat was given out by the chemical reaction.b Iron is more reactive than copper. Iron replaces the

copper and joins with sulphate. The copper waspushed out of its compound to remain on its own.copper sulphate + iron → iron sulphate + copper

c No. Zinc is more reactive than copper. Thecopper cannot push the zinc back out of thecompound.

d The tin coating must have been scratched. Thenwith tin and iron exposed together, the morereactive iron would oxidise first.

e Zinc is more reactive than iron, so the zinc willoxidise instead of the iron.

1 a magnesium + nickel chloride → magnesiumchloride + nickel

b The colour of the solution would graduallychange from green to colourless.

2 a zincb hydrogen

3 a Aluminium is more reactive because itdisplaced the iron from its compound.

b aluminium + iron oxide → iron + aluminium oxide

c A lot of heat is given out during the reactionand the iron melts.

d Powdered aluminium reacts quicker. Moreheat is made more quickly from the reaction.

F4 Who’s top of the league?Greena reactiveb Calcium, lithium and magnesium.c Lithium, calcium, magnesium, zinc, and then in

any order, iron, nickel, copper and gold.d irone Nickel and iron.f i iron

ii copperg Potassium, sodium, lithium, calcium,

magnesium, zinc, iron, nickel, copper, gold.1 a Lithium is very reactive.

b If a test tube was used, the hydrogen givenoff could have shot the liquid out of thetube. In the large beaker the gas could escapeeasily and cause no harm.

c Wear safety glasses, keep any flammablematerials away, any other suitable answer.

2 a Silver is below copper. The copper pushed thesilver from its compound. The solutionbecame green-blue because of the coppernitrate compound in the solution.

b abovec No. Gold is below silver in the reactivity

series. It cannot displace silver from itscompound of silver nitrate.

Reda reactiveb Potassium, sodium, lithium, calcium,

magnesium.c Potassium, sodium, lithium, calcium,

magnesium, zinc.d i Iron displaces nickel and copper from their

compounds.ii Copper is pushed out of its compound by the

other metals.e i iron

ii copperf Less reactive. It did not push any of the other

three metals out of their compounds.g Iron, nickel, copper, gold.h Potassium, sodium, lithium, calcium,

magnesium, zinc, iron, nickel, copper, gold.i i Magnesium will displace zinc from its

compound. Zinc metal will appear alone.ii No reaction.

1 a Silver is below copper. The copper pushed thesilver from its compound. The solutionbecame green-blue because of the coppernitrate compound in the solution.

b copper + silver nitrate → silver + copper nitrate.

c aboved No. Gold is below silver in the reactivity

series. It cannot displace silver from itscompound of silver nitrate.

2 a silver oxide + magnesium →magnesium oxide + silver

b No reaction.c No reaction.d zinc + silver oxide → zinc oxide + silver

3 Put pieces of silver in solutions of sodiumnitrate, scandium nitrate and strontium nitrate.If silver is above sodium, scandium orstrontium, then reactions will occur. Where noreaction occurs, silver is below the metal in thatsolution. Do the same for each of the othermetals in solutions of the other metals. In thecase of sodium use only a very small piece of themetal to put into the other solutions.

F5 Reactivity in actionGreena Yes. Magnesium is above iron in the reactivity

list so it will displace iron from iron oxide.b bottom1 Magnesium is not used for roofing because it is

too reactive. Iron is not used for jewellerybecause it is too reactive.

2 Water contains dissolved salts of differentmetals. If the solutions contained metals belowlead in the reactivity series, the lead would push



F Book answersPatterns of reactivity (continued)

the other metals out of their compounds andtravel through the water as dissolved leadcompounds. Solutions of lead are poisonous.

3 unreactive

Reda It would be a very expensive way to make iron.b Yes. Magnesium is above iron in the reactivity

list so it will displace iron from iron oxide.c It would give out more energy as it is above

aluminium in the reactivity series.d Silver was discovered long before iron and

aluminium. Because it is unreactive it was easierto find this metal uncombined with any othersubstance. Iron and aluminium, however, arequite reactive and are never found as puremetals.

1 a Lead is low in the reactivity series, so it doesnot corrode easily. It can be pressed intothin, watertight sheets that can be mouldedinto shape easily, so it is useful as a roofingmaterial.

b Lead will dissolve in slightly acidic water.Lead solutions are poisonous.

2 a non-metalb Carbon is above iron, copper, zinc and lead

in the reactivity series.c Carbon dioxide.d carbon + lead oxide → lead + carbon dioxidee Carbon is below aluminium.f Aluminium is a reactive metal. It is therefore

never found as the pure metal but always inthe compound form and not easily identified.

F6 Variables togetherGreena Iron is much cheaper to produce than

aluminium. It is also much stronger andhas a greater number of uses than aluminium.

b Oxygen and water.

c There was no oxygen or water in contact withthe nails.

1 Iron in dry air will not rust. Iron in water thatis oxygen free will not rust. Iron in water withoxygen will rust.

2 a There is no water in the desert.b There is no oxygen in swamp water.

Reda i Paint keeps water and oxygen from reaching

the surface of the iron.ii Oil on the surface keeps oxygen and water

from reaching the surface of the iron.iii Aluminium in contact with the air forms a

thin hard coating of aluminium oxide. Thisprevents any further reaction.

iv As aluminium is higher in the reactivityseries than iron, the aluminium will oxidisein preference to the iron.

v There is no water in the desert so iron willnot rust.

vi The rusting of iron will occur very slowlybecause of the low temperature.

vii Rusting will occur very quickly because thereis a lot of water, oxygen and warmth.

b i Yes. Rusting is quicker at highertemperatures.

ii The samples were not observed over theweekend.

iii Individual answers with appropriate reason.iv Check the samples more frequently, have

more water baths at different temperatures,etc.

v If the test tube did not break Terry would seethat there was no rusting during the periodof the experiment.

1 a Washing the underside would clean the saltaway and slow down the rusting.

b Individual answers.2 Individual answers.3 Individual answers.


A-C-Unit Guides 3/Unit F.pdfTitle: A-C-Unit Guides.qxd Author: ganesan Created Date: 6/25/2004 11:27:16 AM

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