Question

The exhibition of highest coordination number depends on the availability of vacant orbitals in the central atom. Which of the following elements is not likely to act as central atom in $MF_6^{3-}$?
(a) B
(b) Al
(c) Ga
(d) In

Answer 1

option a

is the answer

Answer 2

Answer - (a)

Due to absence of d orbital maximum covalency of B is 4.