Final answer:
There are two types of mixtures: heterogeneous and homogeneous. Heterogeneous mixtures have a non-uniform composition, while homogeneous mixtures have a uniform composition throughout.
Step-by-step explanation:
Mixtures fall into two types, based on the uniformity of their composition. The first, called a heterogeneous mixture, is distinguished by the fact that different samples of the mixture may have a different composition. For example, if you open a container of mixed nuts and pull out a series of small samples and examine them, the exact ratio of peanuts-to-almonds in the samples will always be slightly different, no matter how carefully you mix them. Common examples of heterogeneous mixtures include dirt, gravel and vegetable soup.
The second type of mixture is called a homogeneous mixture. In a homogeneous mixture, the composition is uniform throughout the sample. This means that every part of the mixture has the same composition. Examples of homogeneous mixtures include air, simple syrup, and seawater.