A homogeneous mixture is a solid, liquid or gaseous mixture that has the same proportions of its components throughout a given sample (or multiple samples of different proportion). Homogeneous mixtures can have a variable composition. Conversely, a heterogeneous mixture is not uniform in composition, but proportions of its components vary throughout the sample. "Homogeneous '' and "heterogeneous '' are not absolute terms, but depend on context and size of the sample. In chemistry, a homogeneous suspension of material means that when dividing the volume in half, the same amount of material is suspended in both halves of the substance. However, it might be possible to see the particles under the microscope. An example of a homogeneous mixture is air.
matter that is not the same throughout is called
heterogeneous mixture