1. WEATHERING

2. Mechanical weathering
Frost wedging
Exfoliation
Plant roots
abrasion

4. exfoliation

5. Plant roots

6. What happened to these Rocks?
Abrasion

7. Abrasion?

8. Chemical Weathering
Oxidation
Hydrolysis
Dissolution
Plant acids

9. oxidation Metallic elements chemically react with oxygen
The oxidation (rusting) of metals corrodes (weakens) the metals

10. Dissolution
Rocks rich in the mineral calcite (like limestone) are especially vulnerable to chemical weathering. Carbonic acid slowly dissolves the limestone and enlarges cracks, ultimately enlarging them to such an extent that caverns are formed!

11. Acid Rain
Acid rain is rain or any other form of precipitation that is unusually acidic.
(rain is naturally slightly acidic (5.6) because carbon dioxide and water in the air react together to form carbonic acid, a weak acid
“acid rain” refers to precipitation with an pH of lower than 5.6.

12. pH Scale
DRAW this Scale
Acidic
Neutral
Basic

13. pH Scale The pH scale measures how acidic or basic a substance is.
The pH scale ranges from 0 to 14.
A pH of 7 is neutral.
A pH less than 7 is acidic.
A pH greater than 7 is basic.