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To examine cells and learn more about their structure, we need to be able to see them in very fine detail.

Food provides energy and nutrients. The different components of our diet have different sources and functions.

Many chemicals are acidic, neutral or alkaline. We can distinguish one from another using indicators. Acidity and alkalinity are measured on the pH scale.

Most elements are rarely found in their pure form. They are found chemically combined with other elements in compounds. Compounds are often found mixed with other compounds. Mixtures may be separated and analysed.

Atoms and ions bond with each other in two main ways – ionic bonds or covalent bonds. When these bonds are formed the atoms achieve a full outer shell of electrons and become stable.

Materials can have many different physical properties which make them suitable for a range of purposes.

Symbols, formulae and equations help chemists to explain chemical reactions in detail.

Qualitative analysis describes a range of chemical tests that can be carried out to identify a substance.

The rate of reaction increases when reactant particles successfully collide more frequently. Temperature, reactant concentration, size of solid reactant particles (surface area) and catalysts can all affect the reaction rate.

An organic chemical contains the element carbon. There are many different homologous series of organic compounds. Single Award Science focuses on alkanes and alkenes.

Scientific investigations have several stages - planning, collecting data, analysing data and evaluation. It is important to understand how to carry out each stage of the investigation.

Scientific investigations have several stages - planning, collecting data, analysing data and evaluation. It is important to understand how to carry out each stage of the investigation.