Question

Assertion: All halogens undergo disproportionation reaction in alkaline medium.
Reason : All halogens exhibit variable oxidation states.

• A. If both assertion and reason are true and reason is the correct explanation of assertion.
• B. If both assertion and reason are true but reason is not the correct explanation of assertion.
• C. If assertion is true but reason is false.
• D. If both assertion and reason are false.

Answer 1

Answer: (D)

$Cl_{2}, Br_{2}$ and $I_{2}$ undergo disproportionation reaction whereas fluorine does not undergo disproportionation being the most electronegative element. Fluorine cannot exhibit positive oxidation state and hence does not show disproportionation tendency. Fluorine can exhibit only $-1$ oxidation state.