Minerals

Question 1

What is an element?

Answer 1

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

Question 2

What kinds of particles make up atoms?

Answer 2

Electrons, protons, and neutrons

Question 3

What are isotopes of an atom?

Answer 3

Atoms with the same number of protons but a different number of neutrons.

Question 4

What are compounds and why to they form?

Answer 4

A compound is a substance that consists of two or more elements that are chemically combined in specific proportions.

Question 5

What is an ion?

Answer 5

A charged atom, i.e. one that has gained or lost one or more electrons.

Question 6

What is an ionic bond?

Answer 6

A bond formed between positive and negative ions, e.g

Na⁺ + Cl^- = NaCl (table salt)

Question 7

What is a covalent bond?

Answer 7

A bond formed when atoms share an electron (relatively equally).

Question 8

What are common properties of ionic bonds?

Answer 8

They are:

• Rigid solids
• High melting/boiling points
• Poor conductors when solids
• Often good conductors when melted

Question 9

Common properties of covalent bonds?

Answer 9

• Low melting/boiling points (compared to ionic bonds)
• Poor conductors of electricity, even when melted

Question 10

What are metalic bonds?

Answer 10

Bonds that form when electrons are shared by metal ions in a loose cloud. The electrons can move around to conduct electricity.

Question 11

What are properties of metals?

Answer 11

• Good conductor of heat and electricity.
• Shiny (they reflect most of the light that hits them).
• Malleable (can be stretched/formed into wire, etc)

Question 12

What are 5 characteristics of a mineral?

Answer 12

• Naturally occuring (not synthetic)
• Solid (at “normal” temperatures)
• Orderly crystalline structure
• Definite chemical composition (usuall 2+ elements)
• Generally inorganic

Question 13

Describe 4 processes that result in the formation of minerals

Answer 13

• Crystallization from magma
• Precipitation (e.g. limestone)
• Changes in pressure and temperature (recrystallization while still solid)
• Formation from hydrothermic solutions (100-300 C cause chemical reactions to occur which form solids when they cool).

Question 14

What are Silicates?

Answer 14

Minerals formed from a framework of silicon-oxygen tetrahedrons.

Question 15

What are carbonates?

Answer 15

Minerals that contain carbon, oxygen, plus or or more other metalic elements.

Question 16

What are Oxides?

Answer 16

Minerals that contain oxygen and one or more other elements (usually metals)

Question 17

What are sulfates and sulfides?

Answer 17

Minerals that contain sulfur

Question 18

What are Halides?

Answer 18

Minerals that contain a halogen ion (F^-, Cl^-, Br^-, I^-) plus another element.

Question 19

What are properties of minerals (used to ID them)?

Answer 19

• Color
• Streak (color of mineral in powdered form)
• Luster (how light reflects from it)
• Crystal form (visible arrangement of atoms)
• Hardness (Mohs scale 10 hard to 1 soft)
• Breakage:
  
  • Cleavage (tendancy to break along even surfaces)
  • Fracture (uneven breakage)
• Density (mass/volume)
• Other distinctive properties exist…