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There is a wide range of materials, including glass and clay ceramics, polymers, metals and composite materials. They have different physical properties, making them suitable for different uses.

Alloys are mixtures of metals that have useful properties. Addition polymers are made from molecules containing C=C bonds. DNA, starch and proteins are biological polymers.

Different materials can be made from atoms of the same element. The properties of the material depend upon the bonding between the atoms and structure of the substance.

Nanoparticles are 1 nm to 100 nm in size. They have very large surface area to volume ratios. The properties of nanoparticulate substances are different from those of the same substance in bulk.

Many metals oxidise when exposed to air. If exposure continues a metal can become weaker over time. This sort of corrosion may be prevented by a range of methods.

A life-cycle assessment provides a 'cradle-to-grave' analysis of the impact of a manufactured product on the environment. The method of disposal of a product can affect impact on the environment.

Understanding how to approach exam questions helps to boost exam performance. Question types will include multiple choice, structured, mathematical and practical questions.