Question

"All compounds are molecules, but all molecules are not compounds." Justify your answer.

Answer 1

all compounds are molecules as compound are consist of different types of atom in which compound of single type atom also included

But all compounds are not molecules are
only made up of single type of atoms

Compound - H2, CH4
Molecules - H2,O2

Answer 2

All compounds are molecules, but not all molecules are compounds. That is because a molecule can be made up of two atoms of the same kind, as when two oxygen atoms bind together to make an oxygen molecule. However, all compounds are made up of two or more different types of atoms.