What are acids?

A chemical with a pH lower than 7. Acids react with basic substances to form salts and often other substances.
Acids molecules of ions that are proton donors
Acids naturally occur in foods and have a sharp taste to them.








Examples of acids

The three main laboratory acids are. These are all examples of inorganic acids

  • Hydrochloric acid (HCl)
  • Sulphuric acid (H2SO4)
  • Nitric acid (HNO3)






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Some acids are organic. These are known as carboxylic acids. These all have the general formula CnH2n+1COOH  all carboxylic acids have the functional group -COOH

Examples of carboxylic acids include:

  • Methanoic acid (HCOOH)
  • Ethanoic acid (CH3COOH)
  • Propanoic acid (C2H5COOH)

Reactions of acids

Acids always react with alkalis in neutralisation reactions. In these reactions, the acid and the alkali neutralise each other to produce salt and water. the pH of the final product is 7

Some examples of the general reactions that acids can have include:

acid + base --> salt + water

acid + metal --> salt + hydrogen

acid + metal hydroxide --> salt + water

acid + metal carbonate --> salt + water + carbon dioxide









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