Question

How many lone pair of electrons are present on chlorine atom in hypophosphorous acid?

• A. 1
• B. 3
• C. 2
• D. 4

Hint:

Chlorine generally has 3 lone pairs of electrons when it is bonded to other atoms, as in hypophosphorous acid.

Answer 1

The Correct Option is B

Step 1: Understanding the structure of hypophosphorous acid.
In hypophosphorous acid (H\(_3\)PO\(_2\)), the chlorine atom is attached to the phosphorus atom and has lone pairs. To determine the number of lone pairs, we examine chlorine's valence shell. Chlorine has 7 valence electrons, and one of these electrons is involved in bonding with phosphorus, leaving 3 lone pairs of electrons on chlorine.
Step 2: Analyzing the options.
(A) 1: This is incorrect. Chlorine has 3 lone pairs in this structure.
(B) 3: This is correct. Chlorine has 3 lone pairs in hypophosphorous acid.
(C) 2: This is incorrect. Chlorine has 3 lone pairs.
(D) 4: This is incorrect. Chlorine has 3 lone pairs, not 4.
Step 3: Conclusion.
The correct answer is (B) 3.