Question

Calculate the volume of 0.05M KMnO₄ solution required to oxidize completely 2.70g of oxalic acid (H₂C₂O₄) in acidic medium.

Answer 1

Balanced equation for the redox reaction is:

2KMnO₄ + 5(COOH)₂ + 3H₂SO₄ → K2SO₄ + 2MnSO₄ + 10CO₂ + 8H₂O

No of moles oxalic acid = 2.70/90 = 0.03 mole

From the balanced equation, 5 moles of (COOH)₂ = 2 mole KMnO₄

Then 0.03 mole (COOH)₂ = 0.012 moles of KMnO₄.

Now, 0.05 mole of KMnO₄ is present in solution given = 1000 cm³.

0.012 mole of KMnO₄ is present in solution = \(\frac{2}{5}\) = 240 cm³