Question

Pick the odd one out. Give scientific reasons.

Carbon, chalk, sodium, gold

Answer 1

Element:

• A substance made of just one kind of atom.
• Example- Iron is an element made of the same kind of atom.

Compound:

• It is a substance that is composed of two or more elements chemically combined together in a fixed proportion by weight.

Example: Carbon dioxide (${\mathrm{CO}}_2$)

Hence, Carbon, sodium, and gold are elements but chalk is a compound.