Question

The number of moles of KMnO4 that will be needed to react with one mole of sulphite ion in acidic medium is

• A. 2/5
• B. 3/5
• C. 4/5
• D. 1

Answer 1

Answer: (A)

2/5

Answer 2

(1)

2MnO4— + 5SO32– + 6H+ $\longrightarrow$ 2Mn2+ + 5SO42–+ 3 H2O.

$\therefore\frac{2}{5}$mole of MnO4— for one mole SO32—.