KCET · Chemistry · Ionic Equilibrium

In the reaction \( \mathrm{B}(\mathrm{OH})_{3}+2 \mathrm{H}_{2} \mathrm{O} \rightarrow\left[\mathrm{B}(\mathrm{OH})_{4}\right]^{-}+\mathrm{H}_{3} \mathrm{O}^{+} \)
\( \mathrm{B}(\mathrm{OH})_{3} \) functions as

A Bronsted acid
B Lewis acid
C Protonic acio
D Lewis base

Verified Solution

Answer & Solution

Correct Answer

(B) Lewis acid

Step-by-step Solution

Detailed explanation

(B)
Boric acid is a weak mono basic acid (not a protonic acid) but acts as a Lewis acid by accepting electrons from \( O H^{-} \)
ions.

Apply the relevant identity from the chapter and substitute the values established in the previous step, keeping the original constraint in view.

Use the simplified expression to isolate the unknown, then plug the result back into the question setup to confirm the working is internally consistent.

Cross-check against a boundary or limiting case. Both the dimensional balance and the qualitative behaviour at the extreme should agree with the candidate answer.

Combine the steps above to identify the correct option. The remaining choices each fail at least one of the consistency, dimensional, or boundary checks.

Same subject

Match List-I (Laws) with the List-II (Mathematical expressions):

List-I		List-II
(a)	Henry's law	(i)	\(p_1 = p_1^0 x_1\)
(b)	Raoult's law	(ii)	\(p = K_H \chi\)
(c)	First law of thermodynamics	(iii)	\(\Lambda_m = v_+ \lambda_+ + v_- \lambda_-\)
(d)	Kohlrausch's law	(iv)	\(\Delta U = q + w\)

Codes:

KCET 2026 Medium

Explore more questions on app

From KCET

Explore more questions on app

In the reaction \( \mathrm{B}(\mathrm{OH})_{3}+2 \mathrm{H}_{2} \mathrm{O} \rightarrow\left[\mathrm{B}(\mathrm{OH})_{4}\right]^{-}+\mathrm{H}_{3} \mathrm{O}^{+} \)\( \mathrm{B}(\mathrm{OH})_{3} \) functions as

Step-by-step Solution

In the reaction \( \mathrm{B}(\mathrm{OH})_{3}+2 \mathrm{H}_{2} \mathrm{O} \rightarrow\left[\mathrm{B}(\mathrm{OH})_{4}\right]^{-}+\mathrm{H}_{3} \mathrm{O}^{+} \)
\( \mathrm{B}(\mathrm{OH})_{3} \) functions as