GCSE Chemistry is widely used throughout the world by students preparing for GCSE or equivalent examination courses. This edition has been produced to reflect the revised GCSE specifications and to ensure that it is thoroughly up to date. Amendments have been made throughout the text and illustrations to fulfil these aims. In particular, the development of scientific ideas has been expanded, with additional material on the discovery of the periodic table and theories of acids and bases. Further information has been provided on topics, such as instrumental techniques for identifying elements and compounds, the effects of plate tectonics, colloids and carboxylic acids, specifically aspirin, ascorbic acid and citric acid. There is additional material on the technological applications of chemistry, including the extraction and use of titanium and industrial uses of enzymes. Internet research activities have been included. Many of the questions within the text and at the end of each chapter have been updated. Questions from recent past papers have been used for the GCSE exam questions section at the end of the book.