Elements, Compounds and Mixtures — Question 2

The characteristic properties of a pure substance are:

1. They have a definite composition and a definite set of properties like boiling point, melting point, density etc.
2. They are all homogeneous i.e. their composition is uniform throughout the bulk.

We need pure substances to:

1. Prepare medicines.
2. Maintain good health of human beings.
3. Prepare chemicals in laboratories.