Question

Octet rule is not valid for which of the following compounds?

• A. $C{O}_2$
• B. $NO$
• C. $O_2$
• D. $CO$

Answer 1

The correct option is B $NO$

The Lewis structure of $C{O}_2$ is:

Carbon and oxygen obey the octet rule i.e., 8 electrons in the valence shell.

The Lewis structure of $NO$ is:
Oxygen obeys the octet rule but, nitrogen has 7 electrons in the valence shell and does not satisfy the octet rule.

The Lewis structure of $CO$ is:


Carbon and oxygen have 8 electrons in their valence shell.

The Lewis structure of $O_2$ is:

Both the oxygen atoms are satisfying the octet rule.

Hence, the octet rule is not valid for $NO$.