Concept:The VSEPR theory states that electron pairs around a central atom repel each other, and lone pairs exert a stronger repulsive force than bond pairs because they are held closer to the central nucleus.
Formula:$$ \text{Repulsion Order: LP-LP} > \text{LP-BP} > \text{BP-BP} $$
Solution:- Lone pairs (LP) occupy more space in the electron cloud because they are attracted to only one nucleus.
- Bond pairs (BP) are stretched between two nuclei, making their electron cloud more concentrated and exerting less repulsion.
- Therefore, two lone pairs repel each other the most, while two bond pairs repel each other the least.
Why other options are incorrect:- Option A, Option B, Option C: These options invert or scramble the correct descending order of repulsive strength defined by VSEPR theory.
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