1. Chemical Weathering

2. Weathering What is weathering? –Weathering is the disintegration and decomposition of rock at or near the surface of the earth.

3. Weathering Types of Weathering –Mechanical Physical disintegration of rock into smaller fragments, each with the same properties as the original. –Chemical Process by which the internal structure of a mineral is altered by the addition or removal of elements. A chemical process CHANGES or ALTERS the composition of the rock during disintegration

4. Chemical Reactions Characteristics of Chemical Reactions: Bubbling Foaming Change in Temperature Color Change

5. Factors that Effect Chemical Weathering –Temperature Chemical decomposition of rock will be faster in warmer climates. –Hardness Rocks and minerals that are “soft” will weather faster than those that are hard. Limestone is not as hard as granite. –Time Natural chemical weathering is a slow process. The longer a rock has been exposed to chemical decomposition, the more likely it is to be weathered

6. Weathering and Soil Formation Mechanical and Chemical Weathering Promote Soil Formation Soils contain small pieces of rocks and minerals as well as organic material.

7. Soil Formation

8. Chemical Weathering by Acids Acids dissolve some of the minerals in rocks which promotes disintegration and weathering In our environment, chemical weathering can occur as a result from acid rain and acids produced by plant roots and plant decomposition.

9. Effects of Acid Rain