Question

Which of the following is not a diatomic molecule?

• A.
  Nitrogen
• B.
  Oxygen
• C.
  Fluorine
• D.
  Neon

Answer 1

The correct option is D

Neon
The molecules of the given elements exist as given below.

$\begin{array}{cc}\text{Elemenet}& \text{Molecule}\\ \text{Nitrogen}& N_2\\ \text{Oxygen}& O_2\\ \text{Fluorine}& F_2\\ \text{Neon}& \text{Ne}\end{array}$

Diatomic molecules consist of two atoms. Since neon contains only one atom, it is not a diatomic molecule.

Hence, the correct answer is option (d).