What defines a mixture in chemistry?

A mixture in chemistry is defined as a combination of two or more substances that are not chemically combined.

In more detail, a mixture is a physical blend of two or more substances, each of which retains its own chemical identity. The substances in a mixture can be combined in any proportion, and they can be separated from each other by physical means such as filtration, evaporation, or distillation. This is because the substances in a mixture do not react chemically, so no new substances are formed.

There are two main types of mixtures: homogeneous and heterogeneous. A homogeneous mixture, also known as a solution, is a mixture in which the substances are evenly distributed throughout. An example of a homogeneous mixture is salt dissolved in water. On the other hand, a heterogeneous mixture is one in which the substances are not evenly distributed and can be visibly distinguished. An example of a heterogeneous mixture is a salad, where you can see the different ingredients separately.

It's important to note that the properties of a mixture, such as its boiling point or melting point, are often different from the properties of its individual components. This is because these properties depend on the way the substances in the mixture interact with each other.

In summary, a mixture in chemistry is a combination of two or more substances that are not chemically combined. The substances in a mixture retain their own chemical identities and can be separated by physical means.