Question

Which of the following is present in maximum amount in �acid rain� ?

• A. $HNO_3$
• B. $H_2SO_4$
• C. $HCl$
• D. $H_2CO_3$

Answer 1

Answer: (B)

$H_2SO_4$

Answer 2

$H _{2} SO _{4}$ (sulphuric acid) is present in maximum amount in 'acid rain'. Oxides of nitrogen and sulphur, released into the atmosphere from thermal power plants, industries and automobiles are the main sources of acid rain. These oxides on oxidation followed by hydrolysis give sulphuric acid and nitric acid that alongwith $HCl$ are responsible for the acidity of rain. The oxidation reaction is catalysed by particulate matter present in the polluted atmosphere.

$2 SO _{2}(g)+ O _{2}(g)+2 H _{2} O (l) \longrightarrow 2 H _{2} SO _{4}(a q)$

$4 NO _{2}(g)+ O _{2}(g)+2 H _{2} O (l) \longrightarrow 4 HNO _{3}(a q)$