CBSE Class 9 Answered
A molecule is a group of two or more atoms chemically bonded together.
Molecules can be formed either by the combination of atoms of the same element or of different elements bound chemically due to attractive forces between them.
Thus, there are two types of molecules — molecules of elements and molecules of compounds.
A molecule of an element contains two or more similar atoms combined together.
They are classified as diatomic, triatomic, tetra-atomic and poly-atomic molecules, depending on the number of atoms present in it.
A molecule of a compound contains two or more different types of atoms, chemically combined together.
The atoms of different elements join together in definite proportions to form the molecules of the compounds.