Agents of weathering

Chemical

The five agents of chemical weathering are:
–  Water (H2O) dissolves some minerals and rock;
–  Oxygen (O2) combines with other elements in the rock in an oxidation reaction;
– Carbon dioxide (CO2) dissolves in water to make carbonic acid (H2CO3);
– Living organisms produce weak acids that break down or dissolve rock; and
– Acid rain (H2SO4, HNO3,H2CO3) contains acids that break down rock or dissolve it.

 Mechanical

- Plants roots; as they grow they slowly push into cracks of rocks and break them   

- Burrowing of rocks by small animals making holes for habitation of

- people and their machines

- Running water and wind

- Change in temperature which leads to contraction and expansion of rocks hence breakage

weathering

Definitions
weathering- the process whereby rocks break down to form soil particles
mechanical weathering- the process whereby rocks physically breakdown due to environmental factors
chemical weathering-is the breakdown of rocks and minerals due to chemical mechanisms/reactions. it involves transformation of  rocks and minerals into new states/chemical combinations