Patterns in Nature Minerals Test Bank Answers Chapter 3 - Geology Essentials 6e Complete Test Bank by Stephen Marshak. DOCX document preview.
CHAPTER 3: Patterns in Nature: Minerals
LEARNING OBJECTIVES
3A. Explain why the term mineral has a very special meaning in a geologic context.
3B. Describe the processes by which minerals can form.
3C. Explain how geologists organize thousands of different minerals into relatively few classes.
3D. Specify which minerals are the most common ones on the Earth, and describe how they are classified.
3E. Identify common mineral specimens based on their properties.
3F. Distinguish gems from ordinary minerals, and describe how to produce the shiny facets of gems.
MULTIPLE CHOICE
1. Fewer than 50 minerals are ___________
a. | found on the Earth. | c. | found in the crust. |
b. | used for industrial purposes. | d. | commonly found in rocks. |
2. Of the ~4,000 known minerals, the vast majority ___________
a. | are common. | c. | form only near volcanoes. |
b. | are rare. | d. | are characterized as gems. |
3. When a solution becomes oversaturated, new solid particles are said to _______
a. | precipitate from the solution. |
b. | dissolve into the solution. |
c. | react with the solution and produce heat. |
d. | rapidly expand, causing an explosion. |
4. The atomic number of an element corresponds to the __________
a. | number of electrons. | c. | number of neutrons. |
b. | number of protons. | d. | total weight of one atom. |
5. Which of the following choices lists atomic particles ordered from smallest to largest in size?
a. | atom, nucleus, proton, electron | c. | proton, electron, nucleus, atom |
b. | electron, proton, nucleus, atom | d. | atom, electron, nucleus, proton |
6. The atomic mass of an element approximately equals the number of
a. | electrons. | c. | neutrons. |
b. | protons plus neutrons. | d. | protons. |
7. Which of the following are good conductors due to the ability of the electrons in the atoms to move around freely?
a. | metals | c. | silicates |
b. | sulfides | d. | carbonates |
8. Minerals are all naturally occurring solid substances with a definable chemical composition. They must also possess
a. | the ability to be synthesized in the laboratory as well as be found in nature. |
b. | metallic elements, such as iron, calcium, or magnesium. |
c. | metallic luster. |
d. | a fixed crystalline structure (spatial arrangement of atoms and ions). |
9. We distinguish between a mineral and a naturally formed glass (such as obsidian) because
a. | glass is not produced by geologic processes. |
b. | glass is organic. |
c. | glass does not have a fixed crystal structure. |
d. | glass can be made synthetically as well as occur naturally. |
10. Which of the following is a mineral?
a. | petroleum (oil), which is a liquid |
b. | cubic zirconia, which is a synthetic diamond substitute |
c. | ice, which is water in the solid state |
d. | obsidian, a type of volcanic glass |
11. The angles between adjacent crystal faces of the same type of mineral _______
a. | are always the same. |
b. | vary widely among different specimens of the mineral. |
c. | depend on the size of the crystal. |
d. | are 90° for every type of mineral. |
12. Crystals that exhibit well-formed faces are referred to as
a. | pristine. |
b. | anhedral. |
c. | subhedral. |
d. | euhedral. |
13. Minerals in geodes (as seen below) form spectacular euhedral crystals because
a. | all of the elements incorporated in the crystals are in plentiful supply. |
b. | the crystals have abundant room to grow in their hollow surroundings. |
c. | minerals within geodes are always framework silicates. |
d. | minerals within geodes always contain iron. |
14. What is solid-state diffusion?
a. | cooling of a liquid and turning it into a solid |
b. | movement of atoms through a solid to form a new mineral |
c. | bonding of dissolved ions into a solid crystal |
d. | growth of a mineral within or adjacent to a living organism |
15. Where is the most recently formed portion of any crystal always found?
a. | deep within the interior |
b. | on the outer edges |
c. | on whichever side is currently facing upward |
d. | There is no consistent pattern for crystal formation. |
16. Which tool is used to detect the pattern of atoms in a crystal?
a. | magnetic resonance imaging (MRI) |
b. | X-ray diffraction |
c. | thermal ionization mass spectrometry (TIMS) |
d. | cathodized axial tomography (CAT) |
17. When two different minerals have the same chemical formula but different crystal structures, they are said to be
a. | polymorphs. |
b. | polyliths. |
c. | monoliths. |
d. | pseudomorphs. |
18. Diamond and graphite are both polymorphs of
a. | silicon. | c. | magnesium. |
b. | iron. | d. | carbon. |
19. Which of the following minerals is more commonly known as rock salt?
a. | gypsum | c. | halite |
b. | feldspar | d. | quartz |
20. Which of the following describes the process of mineral dissolution?
a. | heating to a temperature where bonds between atoms break |
b. | reacting minerals with reagents to form new minerals |
c. | immersing in water such that atoms or ions separate from crystal faces |
d. | breaking apart bonds to release chemical energy for microbes |
21. Which of the following common minerals is softest?
a. | quartz | c. | talc |
b. | calcite | d. | fluorite |
22. Which of the following common minerals is hardest?
a. | quartz | c. | talc |
b. | calcite | d. | fluorite |
23. The color of a mineral in powdered form is termed
a. | color. | c. | luster. |
b. | specific gravity. | d. | streak. |
24. ______ is a common mineral that can come in different colors, such as clear, milky, rose, and amethyst.
a. | Pyrite |
b. | Halite |
c. | Quartz |
d. | Talc |
25. The way a mineral scatters light is a diagnostic property termed
a. | color. | c. | luster. |
b. | reflectivity. | d. | streak. |
26. The tendency for minerals to break along distinct planar surfaces that have a specific orientation in relation to the crystal structure is called
a. | fracture. |
b. | cleavage. |
c. | specific gravity. |
d. | hardness. |
27. If a mineral lacks cleavage, it will
a. | break along planar surfaces with specific orientations. |
b. | break along irregular or conchoidal fractures. |
c. | not break apart unless melted. |
d. | not break apart unless dissolved. |
28. Hardness refers to a mineral’s ability to resist
a. | breaking. |
b. | being scratched. |
c. | chemically reacting with other substances. |
d. | weathering. |
29. The shape of single crystals or aggregates of many well-formed crystals is known as:
a. | streak |
b. | habit |
c. | luster |
d. | cleavage |
30. A mineral property defined as the density of the mineral sample divided by the density of
water (1.0 g/cm3) is
a. | mass. | c. | luster. |
b. | specific gravity. | d. | streak. |
31. Crystal habit, such as needle-like, platy, or cubic, depends on _________
a. | the color of the mineral’s streak. |
b. | the class the mineral belongs to. |
c. | the wavelength of light reflected off the mineral surface. |
d. | the mineral’s growth rate in different directions. |
32. The image below shows a mineral with hydrochloric acid applied to it. Based on the reaction and presence of gas bubbles, which of the following minerals is the most likely to be _______?
a. | quartz | c. | calcite |
b. | halite | d. | fluorite |
33. Glass and quartz crystals exhibit a smoothly curving, clamshell-shaped fracture pattern termed
a. | glassy fracture. | c. | one-directional cleavage. |
b. | conchoidal fracture. | d. | obtuse fracture. |
34. On the Mohs hardness scale, quartz has a hardness of 7 and calcite has a hardness of 3. This means that _______.
a. | calcite can scratch quartz |
b. | quartz is four times harder than calcite |
c. | calcite is four times harder than quartz |
d. | quartz can scratch calcite |
35. The image below shows a mineral specimen of mica. How many planes of cleavage does mica possess?
a. | one |
b. | two |
c. | three |
d. | many |
36. Using the Mohs hardness scale below, which of the following statements about the actual hardness of minerals is false?
a. | Your fingernail can scratch a sample of gypsum. |
b. | Diamonds are twice as hard as apatite. |
c. | Diamonds are more than seven times as hard as quartz. |
d. | Quartz will scratch anything made of steel. |
37. SiO44–, S2–, and CO32– are all examples of
a. | organic compounds. | c. | anions. |
b. | silicate minerals. | d. | cations. |
38. Minerals are grouped into mineral classes primarily on the basis of
a. | chemistry, specifically the cations within the chemical formula. |
b. | chemistry, specifically the anions within the chemical formula. |
c. | hardness; hard, soft, and medium are the three primary classes. |
d. | the number of cleavage directions present. |
39. Silicate minerals are subdivided into six groups based on the way silica tetrahedra are
a. | bonded to anions. | c. | arranged and bonded. |
b. | bonded to iron atoms. | d. | arranged and charged. |
40. The mineral class that makes up more than 95% of the continental crust is termed the
a. | silicates. | c. | halides. |
b. | carbonates. | d. | oxides. |
41. In silicate minerals, the SiO4 tetrahedron can be linked together by sharing:
a. | silicon atoms. |
b. | cations. |
c. | electrons. |
d. | oxygen atoms. |
42. What type of silicate is the mineral mica?
a. | chain silicate |
b. | framework silicate |
c. | sheet silicate |
d. | ring silicate |
43. What type of silicate is the mineral quartz?
a. | chain silicate |
b. | framework silicate |
c. | sheet silicate |
d. | ring silicate. |
44. Calcite (CaCO3) is in which mineral class?
a. | silicates | c. | oxides |
b. | carbonates | d. | sulfides |
45. Pyrite (FeS2) is in which mineral class?
a. | silicates | c. | oxides |
b. | carbonates | d. | sulfides |
46. The gems sapphire and ruby are two varieties of the mineral corundum (Al2O3). Considering the Mohs hardness of corundum, which mineral listed below would be able to scratch the gems sapphire and ruby?
a. | quartz | c. | topaz |
b. | feldspar | d. | diamond |
47. Which common gemstone results from biomineralization?
a. | diamond | c. | pearl |
b. | garnet | d. | sapphire |
48. Gemstones are often found in pegmatites, which are igneous rocks that are
a. | exceptionally mafic. | c. | exceptionally coarse-grained. |
b. | extrusive, forming from lava. | d. | exceptionally fine-grained. |
49. Diamonds are usually found in a rock called
a. | graphite. | c. | gabbro. |
b. | kimberlite. | d. | diorite. |
50. The diamonds we typically see today in engagement rings do not display their natural crystal faces but rather ________, which are made by grinding the gem on a spinning lap.
a. | striations | c. | cleavage planes |
b. | facets | d. | facades |
1. Why are minerals often referred to as “the building blocks of Earth?”
2. Based on the definition of a mineral, explain why a diamond created in a laboratory is not considered a mineral.
3. Diamond is a polymorph of graphite. What is a polymorph, and explain how graphite is different from a diamond.
4. What are the ways a mineral can crystallize in nature? List and explain each in some detail.
5. What are cleavage and fracture? How are these physical properties similar? How are they different?
6. Some physical properties are more useful for certain minerals than others. Explain how color alone may fail to identify some minerals.
7. Which classes do the common minerals quartz and calcite belong to? What are some of the properties that would distinguish quartz from calcite?
8. Draw and label the atoms in a silicon-oxygen tetrahedron.
9. How are minerals classified? List the major classes of minerals and their pertinent anions.
10. How are diamonds formed?