Question

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

Assertion A: The amphoteric nature of water is explained by using Lewis acid/base concept

Reason R: Water acts as an acid with NH3 and as a base with H₂S.

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

Answer 1

The Correct Option is A

 To determine the correctness and explanation of the given assertion and reason, let's delve into the concepts involved:

1. Assertion A: The amphoteric nature of water is explained by using the Lewis acid/base concept.
   • Water is known to be amphoteric, meaning it can act as both an acid and a base. This behavior is well explained by the Lewis concept of acids and bases, where:
   • A Lewis acid is a species that accepts an electron pair, whereas a Lewis base is a species that donates an electron pair.
   • Thus, the assertion that the amphoteric nature of water is explained using the Lewis concept is true.
2. Reason R: Water acts as an acid with NH₃ and as a base with H₂S.
   • When water interacts with ammonia (NH₃), it donates a proton (H⁺) to NH₃, acting as an acid:
   • When water interacts with hydrogen sulfide (H₂S), it accepts a proton, acting as a base:
   • Therefore, the reason is indeed true and correctly explains how water can act in both roles based on the type of reactants involved.
3. Based on these explanations, both Assertion A and Reason R are true, and the reason provided correctly explains the assertion.

Conclusion: The correct answer is: "Both A and R are true and R is the correct explanation of A."