Question

One mole of mno−4ion can completely oxidise 2.5 mole of c2o2−4

Answer 1

0.2 mol.

Explanation

Redox reactions take place on the basis of equivalence in terms of number of electrons transferred

In acidic medium

KMnO4 ( Mn oxidation state+ VII) gets reduced to MnSO4 (Mn oxidation state+2) i.e. 5 electron change. Thus eqivalent weight is =molar mass /number of electrons transferred i.e.5= 0.2*molar mass

For Fe 2+ oxidized to Fe 3+, 1 electron change

Equivalent weight= molar mass/1.

Thus 0.2 moles of KMnO4 ≈ 1 mole of Fe 2+