• A mixture is a combination of two or more substances. Examples of mixture include soil and air.
• Mixtures can be made by mixing solids and liquids, solids and solids or liquids and liquids.
• A solid that dissolves in a liquid is called a solute.
• A liquid that dissolves a solute is called a solvent.
• A solute and a solvent make a solution.
• The following are examples of solutes, solvents and solutions respectively
• Salt + Water → Salt Solution
• Sugar + Water → Sugar Solution
• Glucose + Water → Glucose Solution

- The ability of a solid to dissolve in a liquid as called solubility. The solubility of a solute depends on the following:

1. Size of the particles of the solute.
2. The amount of the solvent.
3. The temperature of the solvent
4. Stirring of the mixture.

- Soils that cannot dissolve in liquids are called insoluble solids. Examples are soil, wood ash, flour and chalk dust.
- Liquids that mix with other liquids are called miscible liquids.
- Liquids that do not mix are called immiscible liquids.
The following are examples of miscible and immiscible liquids.

• Miscible Liquids: water and milk, cooking oil and paraffin, methylated spirit and milk, petrol and turpentine
• Immiscible Liquids: water and cooking oil, kerosene and water, engine oil and milk, turpentine and ink.

- Magnetic materials are those that are attracted by magnets. They include iron, steel, nickel, cobalt and chromium.
- Non-magnetic materials are not attracted by magnets. Examples are rubber, copper, wood and glass.

- Some methods used to separate mixtures include: winnowing, filtering, evaporation, picking, sieving, decanting, distillationand magnetic separation using a magnet.
- In some cases however, more than one method of separation can be applied to separate some mixtures. - For example, salt and sand can be separated by dissolving, filtration and evaporation.
- Magnetic separation involves separation of magnetic materials from non-magnetic materials.
- The following illustrations show common separation methods.

a) Ilustration of Filtration

b) Ilustration of Evaporation

c) Ilustration of Use of a magnet

d) Ilustration of Decanting

e) Ilustration of Winnowing