Theory behind this practical:

By reacting different metal oxides, carbonates or hydroxides with different combinations of acids, you can make and isolate a specified salt crystal. In this practical, you are going to make and isolate Copper (II) Sulfate crystals.


  1. Add 25cm3 of sulfuric acid into a 100cm3 beaker
  2. Stir in 5g of copper oxide powder ensuring that it is still visible after stirring (in excess)
  3. Set up a filter paper and funnel inside a conical flask
  4. Pour the mixture through the funnel and collect the filtrate
  5. Pour the filtrate into an evaporating basin and place over a water bath
  6. Heat until crystals first appear then turn off the heat
  7. Leave the crystals to grow as they dry. You may remove some, when cool enough, using a spatula and pat them between two paper towels then place into an evaporating dish for next lesson.

Technician notes:

  • 1.0 mol/dm3 Sulfuric acid
  • Copper (II) Oxide powder
  • Spatulas
  • Glass rods
  • 25cm3 measuring cylinders
  • Balances around the lab
  • 100cm3 beakers and 250cm3 beakers
  • Filter funnels
  • Filter paper
  • Small conical flasks
  • Evaporating basins
  • Crystallising dish


Usual lab rules must be adhered to:

  • Lose hair tied up
  • Goggles on throughout the lesson
  • Bags away and stools tucked under
  • Notify the teacher immediately if any spills or breakages occur

For further/more detailed information, check all reagents and practices at CLEAPSS.