Question

The number of moles of $KMn{O}_4$ required to oxidize one equivalent of $KI$ in the presence of sulfuric acid is:

• A. $5$
• B. $2$
• C. $1/2$
• D. $1/5$

Answer 1

Answer: (D)

$1/5$

$10KI+H_{2}S{O}_4+2KMn{O}_4⟶5I_2+2MnS{O}_4+6K_{2}S{O}_4+8H_{2}O$

As 10 moles of $KI$ require 2 moles of $KMn{O}_4$, therefore, one mole of $KI$ require 1/5 moles of $KMn{O}_4$.