Acids, Bases and Mixtures

Water There are many different chemicals used in the household. Water is the most common household chemical; it is a very good solvent and is found in many other chemicals.

Chemical substances used in the home and their functions

The differences between solutions, suspensions and colloids

More solvents used in stain removal

Disinfectants Disinfectants are chemical agents that kill microorganisms (fungi, bacteria and viruses) that may cause the spread of diseases. They reduce the number of microorganisms to a very low level where they are no longer harmful. They do not cause discolouration of the substance on which they are used. Some disinfectants can be used on the skin, but others are best used on non-living material such as kitchen worktops because they can harm us.

Antiseptics Antiseptics also kill microorganisms, but they are designed to be used on the skin without damage.

Deodorants Deodorants are used to mask odours caused by bacteria growing on secretions from the skin, such as sweat. Deodorants work by either removing the odour-forming bacteria or by blocking the sweat glands so that there is no sweat for the bacteria to feed on.

They may also contain borax, which is alkaline, and can remove acidic stains, such as fruit stains.

The action of rubbing the scouring powder on the surface removes anything stuck to the surface, and also parts of the surface. If bleach is present in the powder, there is also a chemical action that removes other substances.

Detergents Detergents on their own, work best on recent dirt and grease. If the grime is ingrained, such as layers of scum on skins and baths, a scouring powder is needed.

The effect of detergent on the environment

The cleaning action of detergents

Abrasive materials Abrasives make use of hard and sharp materials to wear away the surface of softer, less resistant materials.

Various types of abrasive materials