The correct statements from the following are : (A) The decreasing order of atomic radii of group 13 elements is \(\mathrm{Tl}>\mathrm{In}>\mathrm{Ga}>\mathrm{Al}>\mathrm{B}\). (B) Down the group 13 electronegativity decreases from top to bottom. (C) Al dissolves in dil. HCl and liberate \(\mathrm{H}_{2}\) but conc. \(\mathrm{HNO}_{3}\) renders Al passive by forming a protective oxide layer on the surface. (D) All elements of group 13 exhibits highly stable +1 oxidation state. (E) Hybridisation of Al in \(\left[\mathrm{Al}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{3+}\) ion is \(\mathrm{sp}^{3} \mathrm{~d}^{2}\). Choose the correct answer from the options given below:

JEE Main · 2024 · 05 Apr 2024 · Shift 2 · p-Block Elements

The correct statements from the following are :
(A) The decreasing order of atomic radii of group 13 elements is

Tl > In > Ga > Al > B

.
(B) Down the group 13 electronegativity decreases from top to bottom.
(C) Al dissolves in dil. HCl and liberate

H_{2}

but conc.

HNO_{3}

renders Al passive by forming a protective oxide layer on the surface.
(D) All elements of group 13 exhibits highly stable +1 oxidation state.
(E) Hybridisation of Al in

[Al (H_{2} O)_{6}]^{3 +}

ion is

sp^{3} d^{2}

.

Choose the correct answer from the options given below:

(A)(C) and (E) only✓ Correct
(B)(A), (C) and (E) only
(C)(A), (B), (C) and (E) only
(D)(A) and (C) only

Answer: (A)

Solution

(A) Atomic radius generally increases down group 13, but Ga is anomalously smaller than Al (poor shielding by the intervening filled 3d subshell), giving the order

T l > I n > G a > A l > B

— correct.
(B) Electronegativity does not fall monotonically down the group (it is roughly

B > T l > I n \approx G a > A l

) — incorrect.
(C) Al dissolves in dilute HCl liberating

H_{2}

, while concentrated

H N O_{3}

passivates Al by forming a protective oxide film — correct.
(D) The

+ 1

state becomes progressively more important only for the heavier members (inert-pair effect); it is not a "highly stable" state across the whole group — incorrect.
(E)

A l^{3 +}

is six-coordinate in

[A l (H_{2} O)_{6}]^{3 +}

, so the hybridisation is

s p^{3} d^{2}

— correct.
Only C and E are correct.

JEE Main · 2024 · 05 Apr 2024 · Shift 2 · Single correct option

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JEE Main · 2024 · 05 Apr 2024 · Shift 2 · p-Block Elements

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