Paper 1 H - SAMPLE SET 1 Q4
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)