Everyday neutralisation reactions Sodium hydrogen carbonate is produced by the pancreas and liver to neutralise the hydrochloric acid from the stomach when it reaches the small intestine. Aluminium hydroxide and magnesium hydroxide are used in indigestion remedies to neutralise excess stomach acid. Vinegar can be used to neutralise alkaline wasp stings.
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Research this Find out about three more examples of everyday neutralisation reactions.
24.5 Titrations
A titration is a method that is used to investigate reactions between substances. It can be used to investigate the neutralisation reaction between an acid and a base. Titrations use pipettes and burettes to measure volumes of liquids very accurately. A pipette is used to measure an exact volume of base to be added to a conical flask. A burette is used to measure the volume of acid that is added to the base in the conical flask to neutralise it. An indicator is added to the conical flask. As the acid is added to the conical flask the molecules of base in the flask react with the molecules of acid. At the end-point of the titration the last drop of acid neutralises the remaining molecules of base. The indicator changes colour at the point of neutralisation.
Fig. 9 Pipettes and burettes measure volumes of liquids very accurately.
Burette
Fig. 8 An acid and base neutralise each other to produce a salt and water.
Water H2
O
In this reaction the hydrogen of the hydrochloric acid is replaced by a sodium ion from the sodium hydroxide to form the salt sodium chloride.
