Chapter 7 - Exam #2

_____ Chemical weathering breaks up the crust so that physical weathering can attack more surface area. True False

False

_____ Erosion produces sediment and weathering transports it across Earth's surface. True False

False

_____ Because weathering attacks corners from three sides, angular pieces of rock become quickly rounded when exposed to the atmosphere. True False

True

________ Biological weathering produces carbonic acid which chemically weathers soil particles by hydrolysis. True False

True

Soil profiles in temperate climates are characterized by: a. A rich humus layer. b. Calcrete horizons. c. A thin, stony A horizon. d. Aluminum and iron oxides in the upper layer. e. None of the above.

a. A rich humus layer.

The uplift weathering hypothesis: a. Explains global cooling. b. Explains global warming. c. Explains agricultural development. d. Explains orogenesis. e. None of these.

a. Explains global cooling.

Active movement of particles by running water is called a. Fluvial erosion. b. Eolian erosion. c. Mass wasting. d. Gully erosion e. None of these answers is correct.

a. Fluvial erosion

Insoluble residues are: a. Minerals produced by weathering. b. Dissolved compounds resulting from chemical weathering. c. Soils rich in organics. d. Typically dissolved in hydraulic acid. e. All of the above.

a. Minerals produced by weathering.

Iron oxide and aluminum oxide soils are: a. Oxisols. b. Mollisols. c. Andisols. d. Typically in polar soils. e. None of the above.

a. Oxisols

Spheroidal weathering is caused by: a. Sand abrasion in running water. b. Ice crystal growth in cold climates. c. Chemical weathering of angular rocks. d. A combination of slaking and mass wasting. e. None of the above.

c. Chemical weathering of angular rocks.

Karst topography is the result of: a. Soil erosion. b. Biological weathering of silicate rock c. Chemical weathering of carbonate rock. d. Spheroidal weathering. e. All of the above.

c. Chemical weathering of carbonate rock.

The tendency of silicates to weather on Earth's surface is predicted by: a. Mineral texture. b. Environment of deposition. c. Crystallization temperature. d. Tectonic setting. e. Their roundness.

c. Crystallization temperature

Aluminum ore comes from: a. Ice wedging. b. Hot, arid climates. c. Humid tropical settings. d. Physical weathering. e. All of the above.

c. Humid tropical settings.

The most important way silicate minerals chemically weather is: a. Crystal growth. b. Slaking. c. Hydrolysis. d. Dissolution. e. Frost wedging.

c. Hydrolysis

In soil, burrowing organisms turn over and break particles. They also produce organic material that decays and makes__________________________ (a. bauxite b. hydrogen c. carbon dioxide). This combines with water to make________________ (a. kaolinite b. carbonic acid c. chert) which attacks silicate minerals by _____________(a. hydrolysis b. dissolution c. oxidation).

c. carbon dioxide b. carbonic acid a. hydrolysis

The variables that most affect the weathering process are rock composition and ________. a. Topography b. Surface area c. Living things d. Climate e. None of the above.

d. Climate

The major agricultural lands in the United States are based on which soil? a. Vertisols b. Gelisols c. Inceptisols d. Mollisols e. Oxisols

d. Mollisols

The chemical interaction of oxygen with other substances is known as: a. Dissolution. b. Hydrolysis. c. Saturation. d. Oxidation. e. None of the above.

d. Oxidation

Weathering occurs in 3 forms: a. Erosion, tectonics, and uplift. b. Chemical, biological, and physical. c. Crust age, chemistry, and sedimentary minerals. d. Sedimentary quartz, hematite, and alumina. e. None of the above.

b.

A dark-colored layer of mixed mineral and organic matter defines the_________ soil horizon. a. O b. A c. E d. B e. C

b. A

Clay minerals a. Crystallize in cooling magma. b. Are sedimentary minerals that crystallize on Earth's surface. c. Are highly vulnerable to chemical weathering, which is why soil is such a fragile resource. d. Are a relatively minor part of the weathering process. e. All of these answers are true.

b. Are sedimentary minerals that crystallize on earth's surface

_____________(a. Oxidation b. Hydrolysis c. Dissolution) causes feldspar to break down and produce clay.

b. Hydrolysis

In ________, rock breaks down into solid fragments by processes that do not change the rock's chemical composition. a. Chemical weathering b. Physical weathering c. Insolation weathering d. Space weathering

b. Physical weathering

Which of the following statements about carbon dioxide is true? a. It is an important gas that regulates Earth's climate and influences groundwater chemistry. b. The amount present in the atmosphere is affected by the rate of crustal weathering. c. Its decrease has caused net global cooling over recent geologic history. d. It is a greenhouse gas. e. All of the above.

e. All of the above

Which of the following statements about soil erosion is true? a. It is a form of pollution that affects biological communities. b. It is a major problem affecting million of acres of croplands. c. It threatens to impact food production. d. It takes centuries to make soil and only minutes to erode it. e. All of the above.

e. All of the above

Chemical weathering produces new types of sedimentary minerals, including: a. Hematite. b. Chert. c. Clay. d. Calcite. e. All of these are correct.

e. all of these are correct

The pile of rocks that collect at the base of a cliff is called_______________ (a. talus b. humus c. vertisol); the most common process causing rock weathering on a cliff face is__________ (a. salt weathering b. hydraulic action c. abrasion d. ice wedging).

talus ice wedging