Solutions of Acids

Solutions of Acids

Introduction to Acid Solutions

  • Acids are substances that can donate hydrogen ions (H+).
  • When an acid is dissolved in water, it forms a solution.
  • Acids can be categorised into strong acids and weak acids based on their ability to ionise in water.

Strong Acids

  • Strong acids are fully ionised in water.
  • Examples of strong acids include hydrochloric acid (HCl), sulphuric acid (H2SO4) and nitric acid (HNO3).
  • These acids produce a lot of hydrogen ions in solution, making them highly reactive.

Weak Acids

  • Weak acids are only partially ionised in water.
  • Examples of weak acids are ethanoic acid and carbonic acid.
  • These acids produce fewer hydrogen ions in solution, making them less reactive.

Reaction of Acid Solutions

  • In a reaction, hydrogen ions (H+) from the acid combine with other ions to form new compounds.
  • General equations for acid reactions:
    • Acid + Metal -> Salt + Hydrogen gas
    • Acid + Base -> Salt + Water
    • Acid + Carbonate -> Salt + Water + Carbon dioxide

Properties of Acid Solutions

  • Acid solutions are usually corrosive, meaning they can damage or destroy other substances upon contact.
  • Acid solutions are characterised by a sour taste and the ability to turn blue litmus paper red.
  • The pH values of acid solutions are generally less than 7.


  • Always use caution when handling acids due to their corrosive nature.
  • Always wear protective equipment such as gloves and goggles.