Question

Which of the following cannot be hydrolysed?

• A. $SiC{l}_4$
• B. $O{F}_2$
• C. $NC{l}_3$
• D. $S{F}_4$

Answer 1

The correct option is B $O{F}_2$

(a) $SiC{l}_4+4H_{2}O\to Si(OH{)}_4+4HCl$ (by $S_{N}2$ mechanism)
$Si$ has vacant d-orbitals which can accept lone pair from $O$ atom in $H_{2}O$ to form bonds.

(b) $O{F}_2$ hydrolyses in water but the reaction is very slow.
$O{F}_2+H_{2}O\to O_2+2HF$

(c) $NC{l}_3+3H_{2}O\to N{H}_3+3HOCl$
$H_{2}O$ attacks $Cl$ which has vacant $d$-orbitals and not $N$

(d) $S{F}_4+2H_{2}O\to S{O}_2+4HF$
$S$ has vacant d-orbitals which can accept lone pair from $O$ atom in $H_{2}O$ to form bonds.