NEETChemistryp Block Elements (Group 15, 16, 17 & 18)
Suggest reasons why the B–F bond lengths in BF₃ (130 pm) and BF₄⁻ (143 pm) differ.
Options
- AThe presence of the additional F atom in BF₄⁻ leads to increased electron density around the boron atom, causi
- BThe repulsion between the lone pair on the central boron atom in BF₄⁻ causes a longer bond compared to BF₃.
- CThe electronegativity of boron is lower than that of fluorine, resulting in a longer bond length in BF₄⁻.
- DThe symmetry of the BF₄⁻ ion leads to shorter bond lengths compared to the asymmetry of BF₃.
Correct answer
B. The repulsion between the lone pair on the central boron atom in BF₄⁻ causes a longer bond compared to BF₃.
Step-by-step solution
Correct Option is : (B) The repulsion between the lone pair on the central boron atom in BF₄⁻ causes a longer bond compared to BF₃.