Carbonic acid is created when CO2 dissolves in the rain and water vapour in the atmosphere. Due to CO2 being so prevalent in our atmosphere due to human habits polluting the air, the acidic strength...
Rain is not an agent of erosion but water is. Water is the major physical agent that breaks rock. H20 weakens the stenght of the rock. it depends on pemeability. Water can detroy rock also by frost...