Question

1. compare mixtures and substances.

Explanation:

A substance is a pure form of matter with a definite composition and properties. A mixture is a combination of two or more substances where the substances retain their individual identities and properties. Mixtures can be homogeneous (uniform composition throughout) or heterogeneous (non - uniform composition).

Answer:

A substance is pure with definite composition. A mixture is a combination of substances that retain individual identities and can be homogeneous or heterogeneous.