Section 4'1 What is a mineral

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Section 4.1 What is a mineral?
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Key Concepts
Study Guide
Minerals are naturally occurring, solid,
inorganic compounds or elements.

• A mineral is a naturally occurring, inorganic
  solid with a specific chemical composition and a
  definite crystalline structure.
• A crystal is a solid in which the atoms are
  arranged in repeating patterns.

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Study Guide
Key Concepts
Section 4.1 What is a mineral?

• Minerals form from magma or from supersaturated
  solutions.
• Minerals can be identified based on their
  physical and chemical properties.
• The most reliable way to identify a mineral is by
  using a combination of several tests.

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Section 4.2 Types of Minerals
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Study Guide
Key Concepts
Minerals are classified based on their chemical
properties and characteristics.

• In many silicates, one silicon atom bonds with
  four oxygen ions to form a tetrahedron.
• Major mineral groups include silicates,
  carbonates, oxides, sulfides, sulfates, halides,
  and native elements.

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Section 4.2 Types of Minerals
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Study Guide
Key Concepts

• An ore contains a useful substance that can be
  mined at a profit.
• Gems are valuable minerals that are prized for
  their rarity and beauty.

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4.1 Section Questions
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Minerals
All crystalline solids are minerals.
a. true b. false
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4.1 Section Questions
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Minerals
A mineral can be easily broken into cube-shaped
pieces. How many directions of cleavage does this
mineral have?
a. one b. two c. three d. four
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4.1 Section Questions
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Minerals
Magma cools and solidifies deep within Earth.
What characteristic do the resulting mineral
crystals probably have?
a. They are relatively large. b. They are
relatively small. c. They are well
shaped. d. They are all the same mineral.
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4.2 Section Questions
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Minerals
Which group of minerals makes up most of Earths
crust?
a. sulfides b. halides c. oxides d. silicates
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4.2 Section Questions
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Minerals
Carbonate minerals form when one or more metals
bond with a certain negatively charged ion. Which
formula represents this ion?
a. CO2 b. CO42 c. CO32 d. CO
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4.2 Section Questions
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Minerals
Gems include diamonds, rubies, and emeralds. What
characteristics make gems valuable?
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4.2 Section Questions
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Minerals
Possible answer Gems have many characteristics
that make them valuable. Gems have color,
clarity, and other optical properties that make
them beautiful as cut stones. Most gems also are
rare, which increases their value.
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Chapter Assessment Questions
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Minerals
Some hematite has an earthy appearance. Which
property of minerals is being described?
a. texture b. fracture c. color d. luster
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Chapter Assessment Questions
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Minerals
Which mineral fizzes when dilute hydrochloric
acid is applied to it?
a. calcite b. quartz c. gypsum d. pyrite
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Chapter Assessment Questions
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Minerals
Silicate minerals are built from this basic
structural unit. What name is given to the shape
this ion forms?
a. tetrahedron b. cube c. octahedron d. rhombus
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Chapter Assessment Questions
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Minerals
Which mineral is a sulfate?
a. magnetite (Fe3O4) b. halite (NaCl) c. anhydrite
(CaSO4) d. pyrite (FeS2)
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Chapter Assessment Questions
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Minerals
Which mineral group includes minerals that cannot
be broken down chemically?
a. halides b. sulfides c. carbonates d. native
elements
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Standardized Test Practice
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Minerals
Which of these solids is a mineral?
a. coal b. steel c. volcanic glass d. natural
diamond
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Standardized Test Practice
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Minerals
Which term is used to describe the color of a
powdered mineral?
a. luster b. streak c. cleavage d. texture
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Standardized Test Practice
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Minerals
Silica tetrahedra link together to form a variety
of mineral structures. How are the tetrahedra
bound together in these structures?
a. by shared oxygen atoms b. by shared silicon
atoms c. by bonds formed with metals d. by
bonds formed with water
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Standardized Test Practice
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Minerals
About how many minerals have been identified in
Earths crust?
a. 500 b. 1000 c. 3000 d. 5000
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Standardized Test Practice
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Minerals
Some minerals cleave along smooth planes, but
other minerals fracture. What causes minerals to
break in these two different ways?
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Standardized Test Practice
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Minerals
Answer Minerals cleave, or break along smooth,
flat surfaces, when planes of weakness exist
within the mineral. These planes of weakness are
related to the strength of chemical bonds and
structure of the mineral. Minerals that only
fracture, or break in irregular ways, do not have
significant planes of weakness.