Question

Choose the odd one out. Give reasons for your choice.

helium, neon, argon, oxygen, xenon

Answer 1

Oxygen is the odd one out.

Reason - It is a very reactive gas and not part of noble gases.

Noble gases - The group of gaseous non-metals that do not react under general conditions and are found in an independent atomic state.

Examples - helium, neon, argon, and xenon.