Practical questions

You will complete 12 required 'Specified Practical Activities' if you are studying GCSE Chemistry, and 27 if you are studying GCSE Combined Science (nine of these are in Chemistry). These help you develop some key practical techniques in Chemistry.

You could be asked questions about the apparatus, methods, safety precautions, results, analysis and evaluation of these experiments.

There are no 'Specified Practical Activities' in the 'Chemical formulae, equations and amount of substance' section.

Sample question 1 - Foundation

Question

The blue colour of hydrated copper(II) sulfate crystals is due to the presence of water molecules. Using a Bunsen burner, tripod and crucible, these water molecules can be removed by gently heating to form white anhydrous copper(II) sulfate powder.

6.25 g of blue hydrated copper(II) sulfate was gently heated in the crucible until the mass remaining was a constant 4.00 g.

Calculate the mass of water removed during heating. [1 mark]

Question courtesy of Eduqas.

2.25 g [1]

Sample question 2 - Foundation

Question

Use the equation below to calculate the percentage of water in the blue copper(II) sulfate.

percentage of water in blue copper(II) sulfate = mass of water ÷ mass of blue copper(II) sulfate × 100% [2 marks]

Question courtesy of Eduqas.

  • 2.25 ÷ 6.25 × 100 [1]
  • = 36% [1]

Sample question 3 - Higher

Question

Thomas was asked to carry out an experiment to find the formula of an oxide of copper.

  • Thomas weighed an empty test tube and bung
  • he added a sample of the copper oxide and weighed the apparatus again
  • he then connected the tube to a supply of methane
  • he began heating the tube as methane was passed over the hot copper oxide
  • after 5 minutes, he stopped heating and allowed the tube to cool
  • he then weighed the apparatus once more
  • he repeated the heating for two further periods of 5 minutes, cooling and reweighing after each heating

His results are shown in the table.

Mass of bung and tube20.0 g
Mass of bung, tube and oxide of copper25.9 g
Mass of bung, tube and contents after 5 minutes25.1 g
Mass of bung, tube and contents after 10 minutes24.7 g
Mass of bung, tube and contents after 15 minutes24.7 g

Calculate the mass of oxygen in the oxide of copper. [1 mark]

This question has been written by a Bitesize consultant as a suggestion to the type of question that may appear in an exam paper.

1.2 g [1]

Sample question 4 - Higher

Question

Calculate the empirical formula for this oxide of copper.

Show your working. [4 marks]

This question has been written by a Bitesize consultant as a suggestion to the type of question that may appear in an exam paper.

  • mass of copper = 4.7 g [1]
  • Cu 4.7 ÷ 16; O 1.2 ÷ 16 [1]
  • Cu : O ratio is 0.73 : 0.75 [1]
  • therefore empirical formula is CuO [1]