A homogeneous mixture has the same uniform appearance and composition throughout and A heterogeneous mixture consists of visibly different substances or phases.

Air is a homogeneous mixture of the gases, like: nitrogen, oxygen, and smaller amounts of other substances. Its elements are not readily separated or distinguished from one another.

Ice is homogeneous mixture considering it is in solid phase.

Wood is a heterogeneous mixture because all the elements and compounds in a piece of wood are not mixed evenly throughout the wood.

Soil is a heterogeneous mixture because of non-uniform composition of its sample.