• # question_answer Acid rain is due to increase in atmospheric concentration of A)  Ozone  B)         $C{{O}_{2}}$ and $CO$ C)  $S{{O}_{3}}$ and $CO$ D)         $S{{O}_{2}}$ and nitrogen oxide

[d] Both sulphur dioxide $(S{{O}_{2}})$ and nitrogen oxide $(N{{O}_{2}})$ are converted to acids when they combine with water vapour in the atmosphere. These acids return into earth as either wet deposition (acid rain or snow) or dry deposition (sulphate and nitrate salts).