Question

Given below are two statements:


Statement (II): Structure III is most stable, as the orbitals having the lone pairs are axial, where the $ \ell p - \beta p $ repulsion is minimum. In light of the above statements, choose the most appropriate answer from the options given below:

• A. Statement I is incorrect but Statement II is correct
• B. Statement I is correct but Statement II is incorrect
• C. Both Statement I and Statement II are correct
• D. Both Statement I and Statement II are incorrect

Hint:

In reactions involving lone pairs, remember that in \( sp^3d \) hybridization, lone pairs prefer equatorial positions to minimize \( \ell p - \beta p \) repulsion, not axial positions.

Answer 1

The Correct Option is B

To address this question, the provided statements concerning the stability of \(ClF_3\) structures must be evaluated. The question presents three structures, labeled I, II, and III, and requires a determination of the validity of Statements I and II.

1. Statement I: This statement asserts that all three potential structures for \(ClF_3\) can be depicted. This is accurate. \(ClF_3\) exhibits a trigonal bipyramidal molecular geometry with two lone electron pairs. These lone pairs will occupy the equatorial positions to minimize repulsion, leading to the three possible structures.
2. Statement II: This statement contends that Structure III is the most stable, attributing this to lone pairs occupying axial orbitals, thereby minimizing \(\ell p - \beta p\) (lone pair - bond pair) repulsion. This is inaccurate. In a trigonal bipyramidal arrangement, lone pairs preferentially occupy equatorial positions due to reduced repulsion from bond pairs. Consequently, Structure I, with equatorial lone pairs, is more stable than Structure III.

Conclusion: Based on the preceding analysis, Statement I is confirmed as correct, while Statement II is determined to be incorrect. Accordingly, the most fitting response is: Statement I is correct but Statement II is incorrect.