JEE Main 2022 — Chemistry Physical Chemistry

2022mcqmedium

Assertion: The amphoteric behaviour of water is explained by Lewis acid base theory

Reason: water acts as acid with ${\mathrm{NH}}_{3}$ and base with ${H}_{2}S$

Official previous-year question

Held on 25 Jun 2022 · Verified 6 Jul 2026.

Options

A
Both Assertion and Reason are true and Reason is the correct explanation of Assertion.
B
Both Assertion and Reason are true but Reason is NOT the correct explanation of Assertion.
C
Assertion is true but Reason is false.
D
Assertion is false but Reason is true.

Did you get this right?

Solution

$\underset{\mathrm{Acid}}{\underset{⏟}{{H}_{2}O}}+\underset{\mathrm{Base}}{\underset{⏟}{\ddot{N}{H}_{3}}}\rightarrow \mathrm{OH}-+{\mathrm{NH}}_{4}^{+}$

$\underset{\mathrm{Base}}{\underset{⏟}{{H}_{2}O}}+\underset{\mathrm{Acid}}{{H}_{2}S}\longrightarrow {H}_{3}{O}^{+}+{\mathrm{HS}}^{\ominus }$

The amphoteric behaviour of ${H}_{2}O$ is explained by Brønsted theory not the Lewis acid base theory.

So, we can say Assertion is false, but reason is true.

Your note

JEE Main Physical Chemistry in other years

Physical Chemistry 2026 Physical Chemistry 2025 Physical Chemistry 2024 Physical Chemistry 2023 Physical Chemistry 2021 Physical Chemistry 2020 Physical Chemistry 2019 Physical Chemistry 2018 Physical Chemistry 2017 Physical Chemistry 2016 Physical Chemistry 2015 Physical Chemistry 2014

Keep practicing Physical Chemistry

Work through every JEE Main Physical Chemistry PYQ, year by year.

Browse all Chemistry topics

Solution

$\underset{\mathrm{Acid}}{\underset{⏟}{{H}_{2}O}}+\underset{\mathrm{Base}}{\underset{⏟}{\ddot{N}{H}_{3}}}\rightarrow \mathrm{OH}-+{\mathrm{NH}}_{4}^{+}$

$\underset{\mathrm{Base}}{\underset{⏟}{{H}_{2}O}}+\underset{\mathrm{Acid}}{{H}_{2}S}\longrightarrow {H}_{3}{O}^{+}+{\mathrm{HS}}^{\ominus }$

The amphoteric behaviour of ${H}_{2}O$ is explained by Brønsted theory not the Lewis acid base theory.

So, we can say Assertion is false, but reason is true.

JEE Main 2022 — Chemistry Physical Chemistry

Options

Did you get this right?

Solution

Your note

JEE Main Physical Chemistry in other years

More JEE Main Physical Chemistry questions

Other Chemistry topics for JEE Main

Organic Chemistry

Inorganic Chemistry

Keep practicing Physical Chemistry

JEE Main 2022 — Chemistry Physical Chemistry

Options

Did you get this right?

Solution

Your note

JEE Main Physical Chemistry in other years

More JEE Main Physical Chemistry questions

Other Chemistry topics for JEE Main

Organic Chemistry

Inorganic Chemistry

Keep practicing Physical Chemistry