Weathering

Question 1

Weathering definition

Answer 1

The physical or chemical breakdown of materials into smaller materials

Question 2

Physical

Answer 2

• breaks rocks apart without changing their chemical composition
• e.g. freeze-thaw, exfoliation (curved plates of rock are stripped from the rock below)

Question 3

Chemical

Answer 3

• changes the molecular structure of rocks and soil
• e.g. salt weathering, acid rain carbon dioxide from the air is dissolved in rainwater, making it slightly acidic, water washes away, weathering the rock)

Question 4

Biological

Answer 4

• when plants break up rocks with roots or root exudates
• e.g. tree fall, wedging, humic acids (natural decay of plant and animal materials)