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There is a wonderful choice of everyday applications of neutralisation reactions, from those commonly illustrated in chemistry textbooks such as the addition of lime to soil or lakes, to small-scale sherbet type sweets or candy that store a solid acid such as citric acid and sodium bicarbonate ready to dissolve in the mouth with a fizz. The addition of lime (calcium oxide) to acidic soil in order to adjust the pH improves the soil for growing crops or plants, while its addition to acidic lakes similarly adjusts the pH and may help to save marine life.

Calcium hydroxide

Listen to the audio podcast about this most useful compound (or read the transcript) and find out more about calcium hydroxide's wide variety of uses from ancient to modern times – and its intriguing nicknames.

The Lion, the Wich and the Waller

Throughout history, salt has been an essential and valuable commodity. The history of salt production varies, from salt producers who literally undermined their own salt business with their extraction processes, to the origin of words like 'salary' derived from payment in salt.

Saving paper

While the world increasingly relies on reading the electronic word, there is a wealth of historical information desperately needing to be preserved from decay. One major pathway degrading the paper in historical texts is acidic. What chemistry is used to rebuff this acid attack?

How neutralisation is used in diving apparatus

This video clip shows how a neutralisation reaction takes place in modern diving apparatus in order to recirculate unused oxygen. It's worth stressing that carbon dioxide gas is not an acid itself, but is only acidic when it is dissolved in water. (This is explained further in a later topic, The importance of water).