2.6(Spec1) Flashcards
1
Q
Examples of chemical breakdown?
A
- Oxidation
- Carbonation
- Hydrolysis
- Seaweed acid
2
Q
What is carbonation?
A
Dissolution of limestone due to rainfall
Rainfall is slightly acidic (weak carbonic acid)
Produces calcium bicarbonate (carried away dissolved in solution)
3
Q
What is hydrolysis?
A
- Rainwater is slightly acidic due to dissolved CO2
- Minerals breakdown into new minerals changing composition of rock
- formation becomes more unstable
4
Q
How does seaweed acid work?
A
- Seaweed contains sulphuric acid
- when cells break, acid dissolves rock
- lack of bonding between minerals causes rock to crumble
5
Q
Types of mechanical breakdown?
A
- Freeze thaw
- Salt Crystallisation
6
Q
Types of biological breakdown?
A
Boring molluscs
7
Q
How do molluscs breakdown rocks?
A
- Scrape away at rocks to get food
- holes bored into rock become weak points for weathering to act
