C4.2.4 - Neutralisation and the pH scale

• Ions in aqueous solutions

  Acids produce H+ (Hydrogen) ions

  Alkalis produce OH- (Hydroxide) ions
• What is the pH scale?

  The scale measuring the acidity (0-6) or alkalinity (8-14) of a solution.
• How is the pH scale used?

  To measure the acidity or basicity of a solution
• In neutralisation reactions between an acid and an alkali, hydrogen ions react with hydroxide ions to produce water.
• What is the use of universal indicator or wide range indicator to measure approximate pH of a solution?

  Different colours.

  Red to yellow are acidic

  Blue to purple are alkali