Exam 12: Weathering and Soil

The only processes that affect rock are weathering and climate.

When fossil fuels are burned _____,enter the atmosphere to form acid rain.

Hydrogen ions given off by natural acids can disrupt the crystal structure of most minerals,making the structure susceptible to further decomposition.

In arid climates,soils are thin and soil water tends to move ______

________ forms as a chemical weathering product of iron-rich minerals.

Ordinary rain has a pH of about 5.5 to 6 from the carbon dioxide in the atmosphere and from natural sources of acidic sulfur gases.

Because the crystal structure of ice is different from that of water,liquid water expands when it freezes.

____ tend(s)to weather much faster than sandstone.

An acid is a chemical compound that gives off hydrogen ions (H⁺)to a chemical reaction.

Chemical weathering will eventually change a quartz crystal into clay minerals.

The term mechanical weathering refers to changes in a rock that are physical; there is little or no chemical change.

Sand-size grains of feldspar can be preserved in a soil profile over great time periods because of feldspar's resistance to chemical weathering.

The _______ horizon is the uppermost layer of a soil; it consists of organic material.

Water can combine with iron oxide to form ______.

All rocks chemically weather the same way.

The process of chemical weathering is also called ____.

_____ is the mineral least susceptible to chemical attack on the Earth's surface.

______ is wind transported and deposited sediment.

Compared with quartz,minerals that include the positively charged ions of aluminum,iron,magnesium,and calcium are ___ vulnerable to chemical weathering by acidic solutions.

_______ are commonly left after complete chemical weathering.