titration practical

• What are titrations used for?


  Titrations allow you to find unknown concentrations of acids or alkalis
• what is a pipette and what is it used for?


  A pipette is used to accurately measure a certain volume of acid or alkali (normally 25 cm³)
• What is a burette and what is it used for?


  A burette is used to add a very precise amount of alkali or acid to a conical flask, in order to neutralise the acid or alkali in the flask
• why is the tap on the burette it important?


  The tap allows you to add a very precise volume of alkali or acid to the flask, as it controls how quickly it leaves the burette.
• What is the ‘end point’ of a titration?


  The point at which all of the acid or alkali is neutralised and the indicator changes colour
• what safety precautions should be taken while performing a titration?


  wear gloves

  wear safety goggles
• during a titration, why should the flask be placed on a white tile?


  so that you can more easily see the colour change of the indicator as the alkali or acid is neutralised
• during a titration, why should you continuously stir the flask?


  so that the acid/alkali is evenly mixed, and the colour all changes at once
• how can you improve the accuracy of titrations?


  1.repeat the experiment several times until you get concordant results

  2.calculate the mean of the concordant results
• What colour is phenolphthalein in an acidic solution?


  colourless
• What colour is phenolphthalein in a neutral solution?


  colourless
• What colour is phenolphthalein in an alkaline solution?


  pink/red
• What colour is methyl orange in an alkaline solution?


  Yellow
• What colour is methyl orange in an acidic solution?


  red
• Why shouldn’t you use universal indicator for titrations?


  universal indicator doesn’t provide a sudden colour change, so it will be hard to see the ‘end point’