What are two strong inorganic acids that contribute stronglyto the formstion of "acid rain"? Normal rain water would be expected to have pH of about 5.5 So"Acid Rain" is rain with pH lower than this. What greenhouse gas is responsible for normal rainwater having a pH of 5.5 - and write the equilibrium reaction thst is tasking place in the rainwater.please help me answering this quastion.