You have learned previously that pure substances contain only one type of particle and that pure substances can be either elements or compounds. You have also learned that mixtures are made up of more than one type of particle.

In this activity, you will learn more about different kinds of mixtures.

Mixtures can be classified into two main categories: mechanical mixtures and solutions.

The chart you have looked at previously can now have these categories added to it.

Mechanical mixtures are mixtures that contain more than one type of particle. The orange juice with pulp pictured above is one example of a mechanical mixture. Mechanical mixtures can also be called heterogeneous mixtures.

A solution is made when two or more substances combine to form a mixture that is uniform or looks the same throughout. In other words, a solution appears to contain only one kind of particle. The air we breathe is a solution of a number of gases. Other examples of solutions are shampoos, soft drinks, and dish washing detergents. Solutions can also be called homogeneous mixtures.

 Solutions can be gases (e.g., air), liquids (e.g., dish soap), or solids (e.g., metals used in jewellery).

Solutions are made up of solvents and solutes.

The solvent makes up the largest amount of a solution. It is the substance into which another substance dissolves.

The solute makes up the smaller amount of a solution. It is the substance that dissolves into another substance. The more solute there is in a solution, the higher the concentration. For example, the more juice crystals (solute) added to water (solvent), the higher the concentration of the solution.

In salt water, salt is the solute and water is the solvent.