Required practicals

• Independent variable


  • The thing you change
• Dependent variable


  • The other thing that changes as a result which you measure
• Control variables


  • Things that could change but we keep them the same throughout in order to ensure the results are accurate
• Making salt crystals


  1. Heat concentrated sulfuric acid in a beaker

  2. Add excess copper oxide

  3. Filter out unreacted copper oxide

  4. Gently heat the solution in an evaporating basin over a beaker of water on a tripod above a Bunsen burner flame

  5. Solid crystals of copper sulfate are left
• Electrolysis


  1. Put the solution (e.g. sodium chloride) in a beaker

  2. Get two carbon electrodes and put them in the solution making sure they don't touch

  3. Connect the electrodes to a power supply or battery, with the positive terminal (usually red) as the anode and the negative (black) as the cathode

  4. Positive ions (cations) will be reduced at the cathode, negative ions (anions) will be oxidised at the anode
• Measuring temperature changes


  1. Carry out a reaction in a polystyrene cup with a thermometer poked through a lid

  2. Add the other reactant and record the maximum temperature reached

  3. Repeat with increasing volumes of the alkali

  4. Plot two lines of best fit for the rise and fall in maximum temperatures, where they meet tells how much alkali was needed to neutralise the acid