Question

Explain why the B-F bond length in $BF_{3}$ (130 pm) and $BF_{4}^{-}$ (143 pm) differ.

Answer 1

Because of the presence of d orbital.... These varies in bond length

Answer 2

Answer:

In BF3 ‘B’ is sp2 hybridised and in BF4– ‘B’ is sp3 hybridised. Thus, the difference in bond length is due to the state of hybridisation

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