Question

Which of the following reason is correct regarding $[Si{F}_6{]}^{2-}$ is known where, as $[SiC{I}_6{]}^{2-}$ not?

• A. Six large chloride ions can not be accommodated around ${Si}^{4+}$ due to limitation of its size
• B. Interaction between lone pair of chloride ion and ${Si}^{4+}$is not very strong
• C. Both A and B
• D. Presence of d-orbitals in chlorine

Answer 1

The correct option is C Both A and B

$[Si{F}_6{]}^{2-}$ is known, whereas $[SiC{l}_6{]}^{2-}$ is not known because the chlorine atom is much larger than fluorine, which does not allow the six chlorines to surround the silicon due to repulsions between chlorine atoms. Silicon cannot accommodate 6 chlorines around it. Hence, due to interelectronic repulsions between chlorine atoms, the compound $[SiC{l}_6{]}^{2-}$ is unstable and not known.