Question

Which of the following molecule deviates from octet rule with respect to central atom?

• A. $PC{l}_3$
• B. $H_{2}S$
• C. $N{H}_3$
• D. $Xe{F}_4$

Answer 1

The correct option is D $Xe{F}_4$

In $PC{l}_3$, P in atomic state has $5$ valence electrons. $3$ were shared in $PC{l}_3$ and now $P$ have $8$ electrons in valence shell.
In $H_{2}S$, Sulphur needs $2$ electrons to complete octet. So, it shared $2$ electrons with two hydrogen atoms.

$N{H}_3$ is same as in $PC{l}_3$.
In case of $Xe{F}_4$, $Xe$ already have stable octet configuration. On sharing its electrons with $4$ fluorine atoms, it exceeds octet.