Sulfurous acid is the chemical compound with the formula H₂SO₃.
Balanced chemical reaction of sulfurous acid in water:
H₂SO₃(aq) + H₂O(l) ⇄ HSO₃⁻(aq) + H₃O⁺(aq).
or H₂SO₃(aq) ⇄ HSO₃⁻(aq) + H⁺(aq).
Ka is the acid
dissociation constant, which quantifies the extent of acid dissociation (in
this example H₂SO₃) in water.
Ka = [HSO₃⁻]·[H₃O⁺] / [H₂SO₃].
or Ka = [HSO₃⁻]·[H⁺] / [H₂SO₃].
