Question

$H-B-H$ bond angle in ${BH}_4^{-}$ is nearly :

• A. ${180}^o$
• B. ${120}^o$
• C. ${109}^o$
• D. ${90}^o$

Answer 1

Answer: (C)

${109}^o$

It is a example of regular $s{p}^3$ molecule with no lone pairs and all bond pairs same. Hence there is no distortion from the regular tetrahedral angle ${109.5}^o$.