Question

As s-character in a hybrid orbital increases, the bond angle:
(A) increases
(B) decreases
(C) does not change
(D) becomes zero

Answer 1

Hint: In this question we have been given that if s character in a hybrid orbital increases what happens to the bond angle. So, for that as we know s character is directly proportional to the bond angle and inversely proportional to bond length. Use this hint, to get the correct answer.

Complete step by step answer:
We have been asked that if s character in a hybrid orbital increases,
And as we know S orbitals overlap from end to end in most of the situations, it leads to an increase in the bond angle.
Also, the s character of a hybrid orbital is directly proportional to the bond angle and inversely proportional to bond length,
For example:
- In $s{p^3} $: s character is 25%, p character is 75% and the bond angle is ${109^ \circ} $
- In $s{p^2} $: s character is 33.33%, p character is 77.33% and the bond angle is ${120^ \circ} $
- In $sp$: s character is 50%, p character is 50% and the bond angle is ${180^ \circ} $.
From this we can see that as s character is increasing bond angle is also increasing.
The correct answer is option “A” .

Note: An alternative method of solving this question would be taking three compounds other than just $sp, s{p^2}, s{p^3} $ and then with the help of their structure you could explain the same phenomenon.
- Also, be careful as bond angle and bond length have different relations with the S character, so don’t make mistakes due to this.