Chapter 9: Rocks and Minerals October 29 – December 11.

Chapter 9: Rocks and Minerals

October 29 – December 11

Meme Moment

Meme Moment

Meme Moment

Meme Moment

Meme Moment

Meme Moment

Scientist of the Day

Frederick Soddy• Worked with Rutherford• Discovered different types of

radiation• Nobel Prize in chemistry• Started writing books about

economics insteado People thought he was a crackpot,

but his ideas are used todayo Predicted that economy would run

on fossil fuels instead of gold

• Was going to have an element named after him, but “Soddyium” sounds like sodium

Scientist of the Day

Rita Levi-Montalcini• Wanted to be a writer; twin

sister a painter• Friend died of cancer –

decided to be a doctor instead• Lost job in WWII Italy because

she was Jewish• Started working in her

bedroom, then as a refugee• Discovered how nerves grow• Won 1986 Nobel Prize in

medicine

Scientist of the Day

Ada Lovelace• Lord Byron’s daughter• Mother didn’t want her to

be a poet, so she only learned math & logic

• Socialite• Met Charles Babbage

(inventor of computer) at a party

• Wrote the first computer program/algorithm

• Famous science writer too

Scientist of the Day

Clair Patterson• Worked on Manhattan

Project• New techniques for figuring

out the age of artifacts, meteorites, the earth, etc (kind of like carbon dating)

• Age of the earth = 4.5 billion years

• Kept finding lead in everything

• Traced it back to leaded gasoline – it was poisoning people!

Minerals and Molecules

November 9, 20157th grade Chapter 9.1

Atoms• Atom: Smallest unit of matter.

o Except not really, because atoms are made up of ‘subatomic particles’

• Substances made of one type of atom are called elements.

• There are only 118 known elements in the universeo You can see them all on the periodic table (which is a

little out of date)o Each atom has a symbol. E.g. Oxygen is O.

• All of them (except hydrogen and helium) were made in stars

Molecules• Molecule: 2 or more atoms stuck together to

make a substance (chemical). The atoms are joined with chemical bonds

• Chemical bond: force of attraction between 2 atoms

Symbols for Molecules

HBrO4

Each atom has a symbolfrom the periodic table Symbols can be 1 or 2 letters.

First = capital, second = lower case or none

Numbers say how manyNo number = 1

Practice!• How many/what type of atoms do these

molecules have?

• H2O

• CuBr2

• HgCl2• NaCl• KNO3

What do molecules and minerals have in

common?• They are both types of matter, so they are

made of atoms• Minerals and molecules are both substances

o This means they have specific properties that are always the same

• Can sometimes be grown in crystal shapes• Both have chemical formulas (symbols for

writing the name)• Small changes in what they’re made of can be

big changes in their chemical and physical properties

SiO2• SiO2 is a very common substance – sand, glass,

quartz, amethyst• SiO2 can be different minerals

o Dope with small amounts of other elementso Change crystal shape when it’s forming

Properties of Minerals

November 11, 20157th grade Chapter 9.1

Symbols for Molecules

HBrO4

Each atom has a symbolfrom the periodic table Symbols can be 1 or 2 letters.

First = capital, second = lower case or none

Numbers say how manyNo number = 1

Mineral Molecules

CaSO4· 2H2O

This dot shows up in a lot of minerals’ chemical formulas.

It means that for every CaSO4 molecule, there are

2 H2O molecules in the same place. Together, they make gypsum

MineralsMineral: naturally occurring solid that can be formed by inorganic processes, has a crystal structure, and a defined chemical composition

• Defined chemical composition means that it’s a single type of molecule, so you can also call a mineral a substance

• 5 traits to define a mineral

Dioptase (CuSiO3·H2O)

5 Traits of Minerals1. Naturally occurring

o You can make things that look like minerals in a lab, but they’re not “official” minerals unless they’re also found in nature.

2. Solid3. Crystal Structure

o Flat sides, sharp edges (based around prism shapes from math class!)

4. Forms by inorganic processeso You can sometimes form minerals in the body (e.g. kidney

stone), but it’s not an “official” mineral unless you can also make it with things that aren’t plants or animals

5. Definite chemical compositiono You can write a chemical formula for them

Identifying MineralsMinerals are identified mainly by their physical properties

1. Color2. Streak3. Luster4. Hardness5. Density6. Crystal structure7. Cleavage8. Fracture

Marcasite (FeS2)

StreakStreak: color of a mineral’s powder.

• Sometimes different shapes of the same mineral look like different colors, but when you grind them up, it will be the same color

• This used to be very important for making paint!

Lazurite ((Na,Ca)8[(S,Cl,SO4,OH)2 · (Al6Si6O24)])

LusterLuster: how shiny a mineral is/how light is reflected from it

• Uses words like metallic, glassy, earthy, silky, waxy, greasy, pearly

Fluorite (CaF2)

HardnessHardness: how easy it is to scratch a mineral or scratch something else with it

• Measured with Mohs hardness scale• 1= soft, 10=hard

Azurite (Cu3(CO3)2(OH)2)

Cleavage & FractureCleavage: splits easily along flat surfaces

Fracture: what it looks like when it splits

Pyrope (Mg3Al2Si3O12)

Forming Rocks & Minerals

December 1, 20157th grade Chapter 9.1, part 2

MineralsMineral: naturally occurring solid that can be formed by inorganic processes, has a crystal structure, and a defined chemical composition

• Defined chemical composition means that it’s a single type of molecule, so you can also call a mineral a substance

• 5 traits to define a mineral

Dioptase (CuSiO3·H2O)

5 Traits of Minerals1. Naturally occurring

o You can make things that look like minerals in a lab, but they’re not “official” minerals unless they’re also found in nature.

2. Solid3. Crystal Structure

o Flat sides, sharp edges (based around prism shapes from math class!)

4. Forms by inorganic processeso You can sometimes form minerals in the body (e.g. kidney

stone), but it’s not an “official” mineral unless you can also make it with things that aren’t plants or animals

5. Definite chemical compositiono You can write a chemical formula for them

3 Ways to Form Minerals

Crystallization: the process of arranging atoms/molecules so that the substance has a definite crystal structure

1. From solutions2. From cooling lava3. From organic processes

o To be considered a mineral, the same thing has to also form at other times by inorganic processes

o E.g. Calcite can be made by clams and coral for their exoskeleton or in caves as stalactites (and other ways)

Solutions• Not the same thing as fixing a problem!

Solution: similar to a homogeneous mixture, but one substance is dissolved in another substance

• We’re usually talking about things dissolved in water, but it can be anything – technically doesn’t have to even be a liquid

• When substances leave a solution, crystallization occurs

What makes something leave a

solution?• Evaporation

o If you slowly remove the water, it leaves behind the other substance. Bigger crystals instead of sandy particles if it’s slow and not shaken

• Coolingo Usually, hot water can dissolve more of a substance in

the first place. If it gets cold, the substance no longer “fits”

• Chemical changeo If you dissolve one substance and it slowly changes into

something else, the new substance might not have the same solubility (a physical property)

Magma & Lava• Magma is molten rock beneath the earth’s crust• Lava is when it makes it to the surface• Magma & lava contain a lot of oxygen (O) and

silicon (Si), so they form a lot of silicateso Silicates make up most of the earth’s crust

• Type of mineral formed depends on speed, heat, pressure, elements present, etc

• Magma cools slowly• Lava cools quickly, so it makes smaller crystals

Silicates• Depending on how it

cools & what else is present, silicates can form a bunch of different minerals because there are a bunch of different crystal structures possible

Where to find minerals• Depending on how they’re made, some minerals

are more common in certain areas

• If you are in an area with a lot of earthquakes, would you expect more or less minerals to be made from lava?

• If hot water with dissolved substances was pushed through a crack in a rock, what might form?

Classifying RocksDecember 2, 2015

7th grade Chapter 9.2

3 Ways to Form Minerals

Crystallization: the process of arranging atoms/molecules so that the substance has a definite crystal structure

1. From solutions2. From cooling lava3. From organic processes

o To be considered a mineral, the same thing has to also form at other times by inorganic processes

o E.g. Calcite can be made by clams and coral for their exoskeleton or in caves as stalactites (and other ways)

Rocks vs Minerals• Rocks are usually mixtures of minerals and other

componentso Can be 1 mineral or several

• 4 main traits to classify rocks:

1. Mineral composition2. Color3. Texture4. Origin

TextureTexture: the look and feel of a rock’s surface.

• Texture comes from grains• Described by size, shape, and pattern of grains

Grain: particle of mineral or other rock inside a rock.

• Size can be small (fine) or coarse (large)• Shape can be rounded or jagged• Pattern can be nonbanded or banded (flat lines,

swirls, etc)

Rock Origins• 3 major groups for rocks• Determine rock group based on other properties

Igneous rock: formed from cooling magma or lava

Sedimentary rock: forms when particles of other rocks, plants, or animal remains are pressed and cemented together

Metamorphic rock: when a rock is changed by heat, pressure, or chemical change, usually deep underground

Silicates• Depending on how it

cools & what else is present, silicates can form a bunch of different minerals because there are a bunch of different crystal structures possible

Where to find minerals• Depending on how they’re made, some minerals

are more common in certain areas

• If you are in an area with a lot of earthquakes, would you expect more or less minerals to be made from lava?

• If hot water with dissolved substances was pushed through a crack in a rock, what might form?

3 Types of RocksDecember 9, 2015

7th grade Chapter 9.3-9.5

Rocks vs Minerals• Rocks are usually mixtures of minerals and other

componentso Can be 1 mineral or several

• 4 main traits to classify rocks:

1. Mineral composition2. Color3. Texture4. Origin

Rock Origins• 3 major groups for rocks• Determine rock group based on other properties

Igneous rock: formed from cooling magma or lava

Sedimentary rock: forms when particles of other rocks, plants, or animal remains are pressed and cemented together

Metamorphic rock: when a rock is changed by heat, pressure, or chemical change, usually deep underground

Igneous Rocks• Formed from magma or lava, which is high in

silica• When it forms below the crust, it’s called

intrusive• Above the crust, extrusive

Trends (Not Always True):• High in silica = dark rocks• Low in silica = lighter-colored rocks• When it cools quickly, it’s hard to form big

crystals, so very fine grains in the texture.• Hard, dense, and durable = good for arrowheads,

countertops, fortresses

Sedimentary RocksSediment: small, solid particles of rocks or living things

• Sedimentary rocks form when sediment is deposited by water or wind and eventually stuck together

• Usually soft• Sandstone and limestone are important building

materials – sometimes used to make concrete too

Forming Sedimentary Rocks

Weathering & Erosion Deposition Compactio

nCementati

on

3 Types of Sedimentary Rocks

Clastic rock: rock fragments are squeezed together. Classified according to how big the particles are. E.g. conglomerate, shale, sandstone

Organic rock: formed when remains of plants or animals are pressed together. E.g. coal from swamp plants, limestone from shells & skeletons that are high in calcium

Chemical rock: usually formed from solutions. E.g. Rock salt, limestone when it’s from evaporation

Metamorphic Rocks• Start off as sedimentary or igneous rocks, then

are changed by heat, pressure, chemical changes, or a combo of these processes. E.g. marble, slate

• Appearance, texture, and crystal structure of the minerals changes

• Classified by pattern of the grains• Used as building materials, old blackboard, etc.• Most metamorphic rocks are foliated

Foliated: thin, flat layers in a rock

End of Real Notes

Study chemical vs physical changes, rock cycle, and chapter 1-2 also!

Frankenlecture

October 28, 2015

What do these have in common?

• Ada Lovelace• Chemistry• Pee• Frankenstein• Frog legs• Ozymandias• Lord Byron• Batteries• Mary Shelley

The Book• Dr. Frankenstein uses modern

(for the time) science to turn dead parts into a living bodyo Electricity as the élan vital

• His monster is scary• It ends badly

• Extra scary at the time because this might be real scienceo 30 years before, Luigi Galvani

made dead frogs move with electricity

Élan Vital/Vis Vitalis• The spark of life! (Vital force)

At the time (not now):• People thought organic chemistry was totally

different from inorganic chemistry• Organic things like animals, fur, pee, dirt were

different from rocks, metals, etc• Organic things had (or had touched) the spark of

life – the élan vital!• Inorganic could never become organic• Galvani and Volta’s new batteries seemed to

change thato Frankenstein seems like logical progression

Friedrich Wöhler• His experiments failed,

but he found something better

• Was trying to help support Berzelius’ theory, ended up refuting it

• Made urea (pee), which was impossible

• Organic compounds from inorganic stuff

• Changed science!

Science FairDecember 7, 2015

Mandatory for 7th grade

What’s reasonable for science fair?

7th grade HAS to do this. 6th & 8th optional.

• Testing an idea by experiment!• You do it yourself (don’t just do what your parents

tell you or let them take over)• It doesn’t cost too much money – aim for $20 or

less• If you have a really good idea and plans about

how to make it work, Ms. B can help you get lab access at Notre Dame – no guarantees

Are your parents taking over?

• Is it your idea or theirs?• Do you need to use power tools? You should be

the one operating the tools or giving instructions to the Home Depot employee.

• Do you need a lab to complete the project? You should learn how to use/interpret the equipment (supervision expected).

Example• Probably not allowed to use a $500,000 machine,

but a grad student could run your sample and you could figure out how to read it:

Choosing a Project• Make sure it’s an experiment (that answers a question),

not just a demo (that only shows something cool)

Examples of Demos:• Baking soda & vinegar volcano• Marshmallow catapult• Building something from a kit• Rube Goldberg machineExamples of Experiments:• What is the best ratio of baking soda & vinegar to

produce CO2 quickly? What other variables will change the results?

• Does the catapult appear to obey the law of gravity exactly? What other factors are affecting the flight path?

Documentation• The difference between science and randomness

is writing it down.

• Write or type neatly!• All numbers should be written in metric/SI units.• Get a separate notebook or folder for science fair.• Be as objective as possible. (8th grade: use

empirical evidence)• Pictures are good!• When in doubt, write it down!

Lab Report1. Descriptive title – if someone only read this,

would they know what you’re doing?2. Question3. Hypothesis4. Materials list in metric units5. Procedure – how to do your experiment6. Results (Observations)7. Conclusions – what your results mean8. Reflection – sources of error, what to do next, etc

IdeasAdditional information about regionals: • http://sciencefair.nd.edu/

Project ideas: • http://www.education.com/science-fair/middle-sch

ool/• http://www.sciencebuddies.org/science-fair-projec

ts/science_project_ideas.php

• (Note that some of these ideas are better classified as demonstrations – feel free to modify them!)

Getting StartedDue Wednesday, even if you aren’t doing science fair:

• Write down your question, hypothesis, and a rough idea of how you’ll test it

• Ms. B will approve your idea, help you modify it, or ask for another idea

• Backup idea recommended!