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i) What is chemical weathering
ii) State five factors that affect the rate of chemical weathering in equatorial regions
b) Explain the following chemical weathering process
i) Carbonation
ii) Hydrolysis

Answer Text:
a i) - Chemical weathering- is the breakdown or disintegration of rocks as a result of chemical
reaction or changes that cause decay of rocks
ii) - Chemical composition of rocks
- Presence of moisture/ water
- Presence of gases
- Temperature changes
- Rock permeability
- Vegetative matter
b i) - Water in air combines with carbon to form a weak carbonic acid
- Carbonic acid reacts with calcium carbonate in rocks to
form soluble calcium bicarbonate
- Solution is washed away causing weathering to take place
ii) - Water enters the rocks
- Water breaks down into hydrogen ions which combine with minerals
- Rocks break down to form completely new compounds e.g. fluorspar and clay