Titration

• Used to work out the concentration of an acid used to neutralise an alkali
• Stage 1

  • use a pipette to transfer a known volume of sodium hydroxide solution into a conical flask
  • a conical flask reduces the risk of splashing
• Stage 2


  • add five drops of an indicator to the alkali in the flask
  • indicators include methyl orange or phenolphthalein
• Stage 3

  • place the conical flask on a white tile so the colour of the alkali solution can be seen
• Stage 4


  • fill a burette with sulfuric acid
• Stage 5


  • add acid to the alkali until the solution is neutral
  • only add just enough for the colour change to be visible
  • add the acid drop by drop until the solution is
  • it is important to swirl the solution
  • this ensures that the acid and alkali mix
• Colour changes

  • methyl orange - yellow to red
  • phenolphthalein - pink to colourless
• Stage 6


  • read the volume of acid added from the burette
  • make sure that your eye is level with the surface of the liquid
  • repeat the titration several times until two readings are recorded within 0.1 centimetres cubed of each other
  • these are concordant results
  • take a mean of the concordant results for a final volume