Given below are two statements : One is labelled as Assertion A and the other is labelled as Reason R: Assertion A : The stability order of +1 oxidation state of Ga , In and Tl is $\mathrm{Ga}<\mathrm{In}<\mathrm{Tl}$. Reason R : The inert pair effect stabilizes the lower oxidation state down the group. In the light of the above statements, choose the correct answer from the options given below :

(A) Both $\mathbf{A}$ and $\mathbf{R}$ are true and $\mathbf{R}$ is the correct explanation of $\mathbf{A}$.

(B) $\mathbf{A}$ is true but $\mathbf{R}$ is false.

(C) Both $\mathbf{A}$ and $\mathbf{R}$ are true but $\mathbf{R}$ is NOT the correct explanation of $\mathbf{A}$.

(D) $\mathbf{A}$ is false but $\mathbf{R}$ is true.

JEE Main · 2024 · 08 Apr 2024 · Shift 1 · p-Block Elements

Given below are two statements : One is labelled as Assertion A and the other is labelled as Reason R:

Assertion A : The stability order of +1 oxidation state of Ga , In and Tl is

Ga < In < Tl

.

Reason R : The inert pair effect stabilizes the lower oxidation state down the group.

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

(A)Both $A$ and $R$ are true and $R$ is the correct explanation of $A$ .✓ Correct
(B) $A$ is true but $R$ is false.
(C)Both $A$ and $R$ are true but $R$ is NOT the correct explanation of $A$ .
(D) $A$ is false but $R$ is true.

Answer: (A)

Solution

Down group 13 the +1 state becomes more stable (inert-pair effect), so Ga < In < Tl — Assertion A is true. The inert-pair effect is exactly this stabilisation of the lower oxidation state, so Reason R is true and correctly explains A. Option (1).

JEE Main · 2024 · 08 Apr 2024 · Shift 1 · Single correct option

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JEE Main · 2024 · 08 Apr 2024 · Shift 1 · p-Block Elements

Solution

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