Given below are two statements : Statement I: \(\mathrm{S}_{8}\) solid undergoes disproportionation reaction under alkaline conditions to form \(\mathrm{S}^{2-}\) and \(\mathrm{S}_{2} \mathrm{O}_{3}{ }^{2-}\) Statement II: \(\mathrm{ClO}_{4}^{-}\)can undergo disproportionation reaction under acidic condition. In the light of the above statements, choose the most appropriate answer from the options given below:

(A) Statement I is correct but statement II is incorrect.

(B) Statement I is incorrect but statement II is correct

(C) Both statement I and statement II are incorrect

(D) Both statement I and statement II are correct

JEE Main · 2024 · 31 Jan 2024 · Shift 2 · p-Block Elements

Given below are two statements :

Statement I:

S_{8}

solid undergoes disproportionation reaction under alkaline conditions to form

S^{2 -}

and

S_{2} O_{3}^{2 -}

Statement II:

ClO_{4}^{-}

can undergo disproportionation reaction under acidic condition.

In the light of the above statements, choose the most appropriate answer from the options given below:

(A)Statement I is correct but statement II is incorrect.✓ Correct
(B)Statement I is incorrect but statement II is correct
(C)Both statement I and statement II are incorrect
(D)Both statement I and statement II are correct

Answer: (A)

Solution

S_{8}

, sulfur is in the zero oxidation state. Under alkaline conditions it disproportionates:

S_{8} + 12O H^{-} \to 4 S^{2 -} + 2 S_{2} O_{3}^{2 -} + 6 H_{2} O

Sulfur is simultaneously reduced to

S^{2 -}

(oxidation state −2) and oxidized to

S_{2} O_{3}^{2 -}

(average oxidation state +2), so this is a genuine disproportionation. Statement I is correct.

In

Cl O_{4}^{-}

, chlorine is already at its maximum oxidation state, +7. Disproportionation requires the same species to be both oxidized and reduced; since Cl(+7) cannot be oxidized any further,

Cl O_{4}^{-}

cannot undergo disproportionation. Statement II is incorrect.

JEE Main · 2024 · 31 Jan 2024 · Shift 2 · Single correct option

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JEE Main · 2024 · 31 Jan 2024 · Shift 2 · p-Block Elements

Solution

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