What defines a mixture?

A mixture is defined as a physical combination of two or more substances. This definition emphasizes that the components of a mixture retain their individual properties and can be separated by physical means. The substances in a mixture do not undergo a chemical change; instead, they co-exist in their original states.

In a mixture, the materials can be elements, compounds, or both. For example, a salad is a mixture of different vegetables where each retains its properties, and they can be easily sorted or separated. Unlike compounds, where elements are chemically bonded and form a new substance with different properties, mixtures allow for easy separation and do not have a fixed composition.

This understanding of mixtures is fundamental in chemistry, as it sets the stage for exploring solutions, suspensions, and colloids, further distinguishing them from pure substances and compounds.