4.1 - SPECIMEN SET C1 Q4
Parts 4.1 to 4.3 are relevant for Section C4. Part 4.4 is relevant for Section C3.
4) Copper can be produced from copper(II) sulfate solution by two different methods.
Method 1 – Electrolysis
4.1) To produce copper by electrolysis a student has inert electrodes, a d.c. power supply, a switch and electrical wires for the external circuit.
Draw and label the apparatus set up to produce copper from copper(II) sulfate solution by electrolysis. [2 marks]
4.2) Suggest why the colour of the copper(II) sulfate solution fades during the electrolysis. [3 marks]
4.3) Explain how copper is produced from copper(II) sulfate solution by electrolysis. [4 marks]
Method 2 – Displacement
4.4) The chemical equation for the displacement of copper using iron is:
4.1) To produce copper by electrolysis a student has inert electrodes, a d.c. power supply, a switch and electrical wires for the external circuit.
Draw and label the apparatus set up to produce copper from copper(II) sulfate solution by electrolysis. [2 marks]
4.2) Suggest why the colour of the copper(II) sulfate solution fades during the electrolysis. [3 marks]
4.3) Explain how copper is produced from copper(II) sulfate solution by electrolysis. [4 marks]
4.4) The chemical equation for the displacement of copper using iron is:
Calculate the minimum mass of iron needed to displace all of the copper from 50 cm3 of copper(II) sulfate solution.
The concentration of the copper(II) sulfate solution is 80 g CuSO4 per dm3.
Relative atomic masses (Ar): O = 16; S = 32; Fe = 56; Cu = 63.5
Give your answer to 2 significant figures. [4 marks]
The concentration of the copper(II) sulfate solution is 80 g CuSO4 per dm3.
Relative atomic masses (Ar): O = 16; S = 32; Fe = 56; Cu = 63.5
Give your answer to 2 significant figures. [4 marks]
Mass of iron = ________________________ g
(Total for Question 4 = 13 marks)