Final answer:
Mixtures can be classified as either homogeneous or heterogeneous, with the latter being further subdividable by the types of substances mixed, like solids, liquids, or gases, and their separation often involves physical methods.
Step-by-step explanation:
Mixtures can be further separated into subgroups as either homogeneous or heterogeneous. A homogeneous mixture is a mixture in which the composition is uniform throughout the sample, such as air, simple syrup, or seawater. In contrast, a heterogeneous mixture has a non-uniform composition, and its individual components may be discernible, such as in trail mix, salad, or blood (which is also a suspension). Heterogeneous mixtures can often be separated by physical means, like filtration or sorting by appearance.
Matter classification is broad, encompassing pure substances, which have a constant composition and properties, as well as mixtures, which combine elements and compounds while retaining individual properties.