Question

Correct order of molecular mass is:

• A. $O<C<S<N$
• B. $C<S<N<O$
• C. $O<N<C<S$
• D. $C<N<O<S$

Answer 1

The correct option is D $C<N<O<S$

Molecular mass increases across the period from left to right with an increase in atomic number, and also increases down the group.

So, sulphur is positioned below oxygen in the group while oxygen, nitrogen and carbon are successive elements in a period.

Hence, option $D$ is correct.