Question

Helium has ______ atomicity.
1. Tetra-atomic
2. Diatomic
3. Poly-atomic
4. Monoatomic

Answer 1

Correct Answer - Option 4 : Monoatomic

The correct answer is Monoatomic.

• Helium is considered monoatomic because it has 1 atom in its molecule

• Helium is the second lightest atom.
• One nucleus of a Helium atom consists of two protons and two neutrons.
• Helium atoms do not combine into molecules.
• That is why it is called an inert gas, which consists of free atoms.

• Today helium is used instead of hydrogen since it is inert so non-flammable which makes things a lot safer. Hydrogen can ignite very easily when mixed with the oxygen of the surrounding air.