Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R. Assertion A : Boric acid is a weak acid Reason R : Boric acid is not able to release $\mathrm{H}^{+}$ ion on its own. It receives $\mathrm{OH}^{-}$ ion from water and releases $\mathrm{H}^{+}$ ion. In the light of the above statements, choose the most appropriate answer from the options given below.

(A) Both A and R are correct and R is the correct explanation of A

(B) Both A and R are correct but R is NOT the correct explanation of A

(C) A is correct but R is not correct

(D) A is not correct but R is correct

JEE Main · 2022 · 26 Jul 2022 · Shift 2 · p-Block Elements

Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R.
Assertion A : Boric acid is a weak acid
Reason R : Boric acid is not able to release

H^{+}

ion on its own. It receives

OH^{-}

ion from water and releases

H^{+}

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

(A)Both A and R are correct and R is the correct explanation of A✓ Correct
(B)Both A and R are correct but R is NOT the correct explanation of A
(C)A is correct but R is not correct
(D)A is not correct but R is correct

Answer: (A)

Solution

Both statements are correct. Boric acid (

H_{3} BO_{3}

) is a weak Lewis acid that does not donate protons directly. Instead, it accepts

OH^{-}

from water to form

B (OH)_{4}^{-}

, releasing

H^{+}

ions. This mechanism explains why boric acid is weak. Answer: (A).

JEE Main · 2022 · 26 Jul 2022 · Shift 2 · Single correct option

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JEE Main · 2022 · 26 Jul 2022 · Shift 2 · p-Block Elements

Solution

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