Homogenous mixture: The mixtures in which the substances are completely mixed together and are indistinguishable from each other are called homogeneous mixtures. A homogeneous mixture has a uniform composition throughout its mass. It has no visible boundaries of separation between the various constituents. A mixture of two or more miscible liquids is also a homogeneous mixture. All the homogeneous mixtures are called solutions. They consist of only one phase.

Heterogeneous mixture: A mixtures which does not have a uniform composition throughout its mass. It has visible boundaries of separation between the various constituents. The constituents of a heterogeneous mixture can usually be seen easily. They consist of more than one phase. A mixture of two or more immiscible liquids is also a heterogeneous mixture. For example, a mixture of petrol and water is a heterogeneous mixture.