Question

50 ml of aqueous solution of feso4 required 12ml of 0.02M KMnO4 in acid medium for complete oxidation Calculate the molarity of ferrous sulphate solution

Answer 1

Normality = molarity x n-factor
n-factor of KMnO₄ in acidic medium = 5
n-factor of FeSO₄ = 2 

Using the formula N₁V₁=N₂V₂, we get

N₁ x 50 = (0.02 x 5) x 12

N₁ x 50 = 0.1 x 12

N₁ = 1.2/50

N₁ = 0.024

Molarity of FeSO₄ = 0.024/2 = 0.012

Answer 2

Normality = molarity x n-factor

n-factor of KMnO₄ in acidic medium = 5

n-factor of FeSO₄ = 2

Using the formula N₁V₁=N₂V₂, we get

N₁ x 50 = (0.02 x 5) x 12

N₁ x 50 = 0.1 x 12

N₁ = 1.2/50

n1=0.024

molarity is 0.024