Question

In case of mohr salt only Fe ion reacts ,then what is the need to use mohr salt as we can also use FeSO4

Answer 1

Dear Student,

No, FeSO_​4 cannot be used for the titration. This is because FeSO₄ will undergo oxidation of Fe²⁺ to Fe³⁺ in presence of air before the titration can proceed.
On the other hand, Mohr's salt is a double salt and is much stable than FeSO₄. It is less prone to oxidation in presence of air.