Give reason:
Sulphurous acid forms two types of salts in reaction with an alkali.
Sulphurous acid is a dibasic acid and has two replaceable hydrogen ions. Hence, it can form two salts
bisulphite (hydrogen sulphite) and sulphite.
H2SO3 + NaOH NaHSO3 (sodium hydrogen sulphite) + H2O
NaHSO3 + NaOH Na2SO3 (sodium sulphite) + H2O
bisulphite (hydrogen sulphite) and sulphite.
H2SO3 + NaOH NaHSO3 (sodium hydrogen sulphite) + H2O
NaHSO3 + NaOH Na2SO3 (sodium sulphite) + H2O