Chapter 5

-sulfuric acids -carbonic acids (most important) -plant acids

Name at least three natural sources of acid in solution. Which one is most important for chemical weathering?

d. mechanical weathering

Physical disintegration of rock into smaller pieces is called a. chemical weathering. b. transportation. c. deposition. d. mechanical weathering

a. carbonic acid

The single most effective agent of chemical weathering at Earth's surface is: a. carbonic acid (H2CO3) b. water (H2O) c. carbon dioxide (CO2) d. hydrochloric acid (HCl)

d. O horizon

The soil horizon containing only organic material is the: a. A horizon b. B horizon c. C horizon d. O horizon e. E horizon

because there tends to be more air pollution is urban cities that can weather stone buildings.

Why do stone buildings tend to weather more rapidly in cities than in rural areas?

Because of external processes at Earth's surface: -Physical and chemical weathering -erosion -transportation

Why are some minerals stable several kilometers underground but unstable at Earth's surface?

-pressure release: the reduction of pressure on a rock can cause it to crack -frost action: mechanical effect of water freezing on rocks -biological activity: plants growing through rocks.

Describe at least three processes that mechanically weather rock.

granite is an intrusive felsic igneous rock that contains feldspar, quartz, and mica. when exposed to complete chemical weathering in a humid climate, the feldspar breaks down and forms clay minerals (sheet silicates, stable at earth's surface)

Describe what happens to each mineral within granite during the complete chemical weathering of granite in a humid climate. List the final products for each mineral

b. B horizon

Hardpan forms in the: a. A horizon b. B horizon c. C horizon d. E horizon

the surface area of the rock will increase allowing more exposure to chemical weathering

How can mechanical weathering speed up chemical weathering?

soil minerals are very small and easily eroded by wind and water

How do soils erode, and why is it important to minimize soil erosion?

a. loam

Soil with approximately equal amounts of sand, silt, and clay along with a generous amount of organic matter is called: a. loam b. inorganic c. humus d. caliche

a. chemical weathering

The decomposition of rock from exposure to water and atmospheric gases is called a. chemical weathering. b. transportation. c. deposition. d. mechanical weathering

a. clay minerals

The most common end product of the chemical weathering of feldspar is: a. clay minerals b. pyroxene c. amphibole d. calcite

e. quartz does not usually weather chemically

The most common end product of the chemical weathering of quartz is: a. clay minerals b. pyroxene c. amphibole d. calcite e. quartz does not usually weather chemically

d. climate

The most important factor in determining the type of soil that forms is a. parent material b. living organisms c. slope d. climate e. time

-parent material -slope -biological activity -climate -time

What factors affect the formation of soil?

residual: stays where it was formed transported: transported by nature

What is the difference between a residual soil and a transported soil?

d. oxidation

Which is not a type of mechanical weathering? a. frost wedging b. frost heaving c. pressure release d. oxidation