Question

Define elements, compounds and molecules.

Answer 1

Element: An element is a substance that is made entirely of one type of atom.

Example : the element zinc is made up of only zinc atoms.

Molecules: Molecules are a group of atoms covalently bonded to each other.

Molecule can consist of atoms of the same element, or atoms of different elements. e.g. $H_2$

Compound: A compound is a substance that is made up of two or more different elements that are chemically joined, such as $N{H}_3$.