Take home information from this section includes: - What is an element? - A substance that cannot be...

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Take home information from this section includes:- What is an element?

- A substance that cannot be broken down into simpler substances by chemical or physical means

- 112+ known elements- 92 occur naturally, rest are made in the lab- Organized by properties into the Periodic Table

CH 2 MineralsSection 2.1 Matter

CH 2 MineralsSection 2.1 Matter- What particles make up atoms?

- Atoms are the smallest particles of matter- Made up of protons, neutrons, and electrons

CH 2 MineralsSection 2.1 MatterWhat are Isotopes?

- have the same number of protons but varying numbers of neutrons.

- important because same element has different isotopes

What are compounds and why do they form?A compound consists of two or more elements that

are chemically combined in specific proportions.Important because compounds have different properties

than the elements that make them up

CH 2 MineralsSection 2.1 Matter

Mineralsthe building blocks of rocks

Mineral Characteristicsnatural inorganic soliddefinite compositioncrystal structure

Mineral Formation

4 major processes by which minerals form:

1. Crystallization from magma- cooling magma causes minerals to crystallize

2. Precipitation Minerals dissolve out

of evaporated water; precipitated

3. Pressure and Temperature

Change in pressure and temperature cause an existing mineral to recrystallize while still solidMuscovite

Talc

4. Hydrothermal Solutions

A hot mixtures of water with substances dissolved in them. When they come in contact with existing minerals- a chemical reaction occurs forming a new mineral

Bornite

Mineral CompositionMinerals are grouped or classified based on

their composition. There are 6 groups1. Carbonates - contain

carbon, oxygen, and one ore more metallic element

2. Silicates- formed from silicon and

oxygen - elements combined to form

a silicon tetrahedron, 1 silicon atom and 4 oxygen atoms

- formed from cooling magma

- either near the surface (few crystals) or deep below surface (larger crystals)

3. Oxides

- Minerals that contain oxygen and one or more other element(s)

4. Sulfates and Sulfides- Minerals containing

sulfur

Gypsum

Pyrite

5. Halides

-minerals containing halogen ions plus one or more other elements

Halite

6. Native Elements

Minerals that exist in a relatively pure form

i.e. Gold, silver, copper

Gold crystal structure

Mineral Properties

Mineral PROPERTIES are used to identify minerals based on specific characteristics

Luster

Streak

Color

Specific Gravity

Cleavage & Fracture

Hardness

Magnetism

Fluoresence

Streak color of a mineral in its powder form

Coloroften not a good property for Iding

Lusterhow light is reflected from the surface of a mineral

Cleavage- tendency to break along flat, even surfaces (mica)Fracture- uneven breakage (quartz)

Mica has cleavage in one direction

Specific Gravity- ratio of a mineral’s density to the density of water

Density= Mass (g) Volume (mL or cm3)

Density of water is 1 g/cm3

Specific Gravity is a ratio, no units

Hardness- measure of resistance of a mineral being scratched

MagnetismMagnetite

Fluorescence

Double RefractionCalcite

Smell Sulfur