Download Earth Science study guide: Unit 3 (Chapters 8

Earth Science Study Guide: Chapter 2
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Vocabulary:
Atom – smallest unit of an element
Molecule – two or more atoms chemically combined (O2)
Compound – two or more elements chemically combined (SiO2)
Physical properties – observable characteristic of a substance that will not change the chemical
composition of the substance
5. Chemical properties – describes how a substance interacts with other substances to create a new
substance
6. Salt – compound formed from an alkali metal (group 1) and a halogen (group 17)
1.
2.
3.
4.
Concepts:
 Recognize compounds of silicates and non-silicates by their chemical formula.
 Recognize elements versus compounds.
Cu (copper) & Ag (silver) are elements
Compounds contain more than one element
SiO2 is a silicate called quartz
Al2O3 Aluminum oxide is a non-silicate
Vocabulary:
1. Mineral – natural inorganic solid found in earth’s crust
2. Inorganic – NOT made up or produced by living organisms or their remains
3. Silicate – mineral that contains atoms of silicon and oxygen (ex: quartz, feldspar)
4. Non-silicate - minerals that do not contain silicon (only 4% of the Earth’s minerals)
5. Crystal - a natural shape of specific geometric arrangement
6. Streak - color of a mineral in powder form
7. Density - the ratio of the mass of a substance to its volume
8. Luster - light reflected from the surface of a mineral (metallic & non-metallic)
9. Fluorescence - ability to glow under UV light
10. Phosphorescence - minerals that continue to glow even after exposure to UV light stops
11. Cleavage - the surface on which a mineral breaks
12. Fracture -minerals that break unevenly, in irregular pieces
13. Hardness - the ability to resist scratches
14. Loadstone - a natural magnet; form of magnetite
OVER
Concepts:
Characteristics of Minerals:
1.
2.
3.
4.
5.
Naturally occurring (a diamond made in a lab is NOT a mineral)
Solid
Inorgainc (not made up or produced by living organisms or their remains)
Definite chemical composition (halite is always NaCl)
Definite crystal structure (Silicates always form a silicon-oxygen tetrahedron)
Know the most common elements found in the Earth’s crust and their relative amounts:
(you do NOT need to memorize the %)
o oxygen (46%)
o silicon (28%)
o aluminum (8%)
o iron
(5%)
(Example: oxygen is the most common element, aluminum is the most common metal)
< 4% calcium, sodium, potassium, magnesium
Silicates:
 Of the over 3000 minerals, only 20 are common. 10 minerals make up 90% of the earth’s crust.
 Silicates (contain Silicon and Oxygen) make up 97 % of the earth’s crust.
 Quartz and Feldspar alone make-up 50% of the earth’s crust.
Nonsilicates:
 Identify the major groups of nonsilicate minerals
carbonates, halides, native elements, oxides, sulfates, and sulfides (p. 47-49)
 Non-silicates make up about 4% of the earth’s crust
Mineral identification:
 Understand and identify the characteristics of minerals for identification:
color, streak, luster, cleavage/fracture, hardness, crystal shape, density
 Be able to use Mohs’ scale of hardness [1 is softest (talc), 10 is hardest (diamond)]
Order of hardness using scratch test: fingernail, copper, steel, glass, quartz
 Recognize these crystal shapes (p. 166):
isometric (3 axis of equal length at 90º angles) – galena, halite, and pyrite
hexagonal (intersect at 60º angles) – quartz and calcite
 Identify special or unusual properties of some elements:
magnetism – loadstone
fluorescence – calcite
radioactivity - uranium
double image – calcite
Review homework assignments and lab reports.