Q. Boron cannot form which one of the following anions?
A) $BF_{6}^{3 -}$
B) $BH_{4}^{-}$
C) $B(OH)_{4}^{-}$
D) $BO_{2}^{-}$
Explanation
(a)
[image:11_image12.emf]
Due to absence of $2d$-orbital, maximum covalency is four.
Thus $BF_{6}^{3 -}$is not formed,
Thus (a) is not formed.
$BH_{4}^{-}(BH_{3} + H^{-})$
$B(OH)_{4}^{-}(B(OH)_{3} + OH^{-})$
and $BO_{2}^{-}$are formed.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.