Explanation

Depending on climate conditions, tiny particles of nitrogen and sulphur oxides may be airborne for a while and then fall to earth as dry acid deposition. Most of sulphur and nitrogen dioxides dissolve in atmospheric water to form weak solutions of $H_{2}SO_{4}$and $HNO_{3}$. Winds can distribute them over great distances before they fall to earth in rain and now, this is called wet acid deposition.