Question

The number of moles of acidified $KMn{O}_4$ required to convert sulphite ion into sulphate ion is:

• A. 2/5
• B. 3/5
• C. 4/5
• D. 1

Answer 1

The correct option is A 2/5

$2KMn{O}_4+5H_{2}S{O}_3\to K_{2}S{O}_4+2MnS{O}_4+2H_{2}S{O}_4+3H_{2}O$

2/5 moles of acidified $KMn{O}_4$ will convert sulphite ion into sulphate ion.

Hence, the correct option is $A$.