Answer
Acid rain is a rain that has a lower pH value because it contains higher amount of acidic compounds. Sulfur dioxide and nitrogen oxide in the atmosphere react with water and produce sulfurous and nitric acids.
Sulfur dioxide is released during the eruption of the volcano, when released hydrogen sulfide reacts with oxygen molecules from the air:
$2H_{2}S + 3O_{2} -> 2SO_{2} + H_{2}O$
Sulfur dioxide reacts with water molecules and forms sulfurous acid.
$SO_{2} + H_{2}O -> H_{2}SO_{3}$
Nitrogen oxides are made during lightning, when high temperature causes nitrogen and oxide molecules to react:
$N_{2} + O_{2} -> 2NO$
Nitric oxide further reacts with oxygen:
$2NO + O_{2} -> 2NO_{2}$
In the atmosphere, acid rain is formed:
$2NO_{2} + H_{2}O -> HNO_{2}+HNO_{3}$
Work Step by Step
Acid rain is a rain that has a lower pH value because it contains higher amount of acidic compounds. Sulfur dioxide and nitrogen oxide in the atmosphere react with water and produce sulfurous and nitric acids.
Sulfur dioxide is released during the eruption of the volcano, when released hydrogen sulfide reacts with oxygen molecules from the air:
$2H_{2}S + 3O_{2} -> 2SO_{2} + H_{2}O$
Sulfur dioxide reacts with water molecules and forms sulfurous acid.
$SO_{2} + H_{2}O -> H_{2}SO_{3}$
Nitrogen oxides are made during lightning, when high temperature causes nitrogen and oxide molecules to react:
$N_{2} + O_{2} -> 2NO$
Nitric oxide further reacts with oxygen:
$2NO + O_{2} -> 2NO_{2}$
In the atmosphere, acid rain is formed:
$2NO_{2} + H_{2}O -> HNO_{2}+HNO_{3}$
