3. Abrasion is when the the wind picks up sand and rocks and drives them against the larger rocks and wares them out.
4. Carbonic acid is when a weak acid, H2O, is formed in solution when carbon dioxide is dissolved in water.
5. Chemical weathering is when you have a rock and it sits out in the rain, heat, or wind and the weather changes its form by changing the color of the outer part or the rust.