test-1 chemistry

1

1 The diagram shows models of various elements.

B

ED

A C

(a) Define the term element.

[1]

(b) Which one of the models A to E represents a solid containing diatomic molecules?

[1]

(c) Which two of the models A to E represent gases?

and [1]

(d) (i) Which one of the models A to E represents diamond?

[1]

(ii) State the name of the element present in diamond.

[1]

(iii) State a use of diamond other than in jewellery.

[1]

2

(e) Structure E is a metal. State three physical properties which are characteristic of all metals.

[3]

(f) Metals are sometimes mixed with other elements in order to change their properties. (i) What is the name given to a mixture of metals with other elements?

[1]

(ii) Match up the metals in the boxes on the left with their uses on the right. The first

one has been done for you.

for making chemical plants

for plating tin cans

for car bodies

for electrical wiringin houses

for aircraft bodies

tin

mild steel

stainless steel

aluminium

copper

[4]

3

2 The electronic structures of various atoms are shown below.

A B

D E

C

(a) (i) Which one of these structures A to E represents a noble gas?

[1]

(ii) Which two of these structures represent atoms from the same Group of the

Periodic Table?

and [1]

(iii) Which one of these structures represents an atom with an atomic number of 8?

[1]

(iv) Which one of these structures forms a stable ion by gaining one electron?

[1]

(v) Which one of these structures is in Period 3 of the Periodic Table?

[1]

4

(b) Complete the following sentences using words from the list.

chlorine diamond high low sharing

sodium strong transfer weak

Covalent bonds are formed by the of pairs of electrons. Simple

covalent molecules such as and bromine have

melting points. Giant covalent structures such as have many

bonds and have high melting points. [5]

(c) The simplest covalent molecule is hydrogen. (i) Draw a diagram to show how the electrons are arranged in a hydrogen molecule. [1] (ii) Describe a test for hydrogen.

test

result [2]

5

3 The structures of some elements and compounds are shown below.

S

S S

S

S

SS

SH HC

H

H

H C

H

H

H

H

C H

NH H

H

Pb Pb Pb Pb Pb

Pb Pb Pb Pb Pb

Pb Pb Pb Pb

Na+

Cl

Na+

Cl

Na+

Cl

Na+

Cl Na+

Cl

Na+

Cl

Na+

Cl

Na+

Cl

Na+

Cl

Na+

Cl

A B C

D E F

(a) Answer these questions using the letters A to F.

(i) Which structure is ethane? [1]

(ii) Which structure contains ions? [1]

(iii) Which structure is a gas that turns moist red litmus paper blue? [1]

(iv) Which structure is sodium chloride? [1]

(v) Which structure is the main constituent of natural gas? [1]

(vi) Which two structures are organic compounds? [1]

(vii) Which two structures are elements? [1]

6

(b) Structure F is lead. (i) What is the source of the small amount of lead present in the air?

[1]

(ii) State an adverse effect of lead on health.

[1]

(c) Structure A is sulphur. Explain why burning fossil fuels containing sulphur is harmful to

the environment.

[2]

[Total: 11]

7

4 Clean air contains a number of different gases. (a) State the names of the two gases which make up most of the air.

[2]

(b) A sample of air is drawn through the apparatus shown below.

white (anhydrous)

copper sulphate

limewater

air

to

suction

pump

heated copper

(i) When the air is drawn through the apparatus, the lime water turns milky. Which

gas turns lime water milky?

[1]

(ii) The white (anhydrous) copper sulphate turns blue. State the name of the

substance which turns white copper sulphate blue.

[1]

(iii) Oxygen is removed from the air by passing it over heated copper. Complete the equation for this reaction.

2Cu + CuO [2]

8

(c) Pure air contains about 1% argon. (i) In which Period of the Periodic Table is argon?

[1]

(ii) State the name of the Group of elements to which argon belongs.

[1]

(iii) Draw the electronic structure of argon. [1] (iv) Why is argon used in lamps?

[1]

(v) An isotope of argon has a mass number of 40. Calculate the number of neutrons in this isotope of argon.

[1]

(d) A small amount of xenon is present in the air. A few compounds of xenon have been made in recent years. Calculate the relative molecular mass of xenon difluoride, XeF2. [1]

9

(e) The structure of another compound of xenon is shown below.

XeF F

F FO

(i) Write the simplest formula for this compound of xenon.

[1]

(ii) Describe the type of bonding in this compound.

[1]

[Total: 14]

10

5 The halogens are a group of elements showing trends in colour, state and reaction with other halide ions.

(a) Complete the word equation for the reaction of chlorine with aqueous potassium

bromide.

chlorine + potassium bromide + [2]

(b) Explain why an aqueous solution of iodine does not react with potassium chloride.

[1]

(c) The table shows the properties of some halogens.

halogen state at room temperature

colour boiling point / C density of solid / g cm-3

fluorine gas yellow 1.51

chlorine green 35 1.56

bromine liquid red-brown 59

iodine solid 184 4.93

(i) Complete the missing spaces in the table. [2] (ii) Suggest values for

the boiling point of fluorine,

the density of bromine. [2]

(d) How many electrons does an atom of fluorine have

(i) in total,

(ii) in its outer shell? [2]

(e) State a use for chlorine.

[1]

[Total: 10]

11

6 The diagram shows the structures of some substances containing carbon.

O C O

C CH

H

H

H

C

H

HHH

C C O HH

H

H

H

H

CC

C CC

C

CC C

C CC

C

C CC

CC

C CC

C

CC

C CC CC

C CC C

CC

C CC

Ca2+CO23 Ca2+CO23 CO23

Ca2+ Ca2+CO23 CO23 Ca2+

Ca2+CO23 Ca2+CO23 CO23

Ca2+ Ca2+CO23 CO23 Ca2+

A B C

D E F (a) Answer these questions using the letters A, B, C, D, E or F.

(i) Which one of these structures is ionic? [1]

(ii) Which one of these structures represents ethanol? [1]

(iii) Which one of these structures represents a gas which

turns limewater milky? [1]

(iv) Which one of these structures is an unsaturated

hydrocarbon? [1]

(b) Describe a chemical test for an unsaturated hydrocarbon.

test

result [2]

12

(c) State the chemical name of structure B.

[1]

(d) Structure F has several uses. Which one of the following is a correct use of structure F? Tick one box.

for cutting metals

as a lubricant

for filling balloons

as an insulator [1]

(e) The structures A to E are compounds. What do you understand by the term compound?

[1]

(f) State the type of bonding in structure A.

[1]

[Total: 10]

13

7 Iron has several isotopes. (i) What do you understand by the term isotopes?

[1]

(ii) The table shows the number of subatomic particles in an atom of iron.

type of particle number of particles relative charge on the particle

electron 26

neutron 30

proton 26

Complete the table to show the relative charge on each particle. [3] (iii) State the number of nucleons in this isotope of iron.

[1]

(a) Some isotopes are radioactive. State one industrial use of radioactive isotopes.

[1]

(b) Iron reacts with very dilute nitric acid.

Fe + 2HNO3 Fe(NO3)2 + H2

Write a word equation for this reaction. [1] [Total: 13]

14

(c) When concentrated seawater is electrolysed, chlorine is formed at one of the electrodes. (i) To which Period in the Periodic Table does chlorine belong?

[1]

(ii) Draw the electronic structure of a chlorine molecule. Show only the outer electrons. [2] (d) Drinking water can be obtained by purifying seawater. Explain why distillation rather than filtration is used to purify seawater for drinking.

[2]

[Total: 11]

15

8(a) Chlorine is in Group VII of the Periodic Table. When chlorine reacts with a solution of potassium bromide, the solution turns a

reddish brown colour. (i) Write a word equation for this reaction. [2] (ii) Explain why iodine does not react with a solution of potassium bromide.

[1]

(b) When chlorine reacts with sodium to form sodium chloride, energy is released. (i) State the name given to a reaction which releases energy.

[1]

(ii) What type of bonding is present in sodium chloride?

[1]

(iii) Explain what happens in terms of electron transfer when a sodium atom reacts with

a chlorine atom.

[2]

[Total: 14]

16

9 Pure dry crystals of magnesium sulphate can be made by reacting excess magnesium powder with dilute sulphuric acid.

(a) During the reaction, bubbles of a colourless gas are given off. State the name of this gas.

[1]

(b) (i) Why is excess magnesium used?

[1]

(ii) How is the excess magnesium removed from the reaction mixture?

[1]

(c) Describe how you can obtain pure dry crystals of magnesium sulphate from a solution

of magnesium sulphate.

[2]

(d) (i) Describe one other reaction that makes magnesium sulphate.

[1]

(ii) Write a word equation for the reaction you suggested in part (d)(i). [1] (iii) Magnesium sulphate can be used as a medicine. Explain why the chemicals used

in medicines need to be as pure as possible.

[1]