An electrolytic cell is set up to purify a sample of impure blister copper using an aqueous copper(II) sulfate electrolyte, as shown in the diagram below.
Which combination correctly identifies the material used for the positive electrode (anode) and the primary oxidation half-equation occurring at that electrode to allow purification?
Anode material: Impure copper; half-equation: Cu(s)→Cu2+(aq)+2e−Cu(s) \rightarrow Cu^{2+}(aq) + 2e^-Cu(s)→Cu2+(aq)+2e−
Anode material: Pure copper; half-equation: Cu2+(aq)+2e−→Cu(s)Cu^{2+}(aq) + 2e^- \rightarrow Cu(s)Cu2+(aq)+2e−→Cu(s)
Anode material: Graphite; half-equation: 2H2O(l)→O2(g)+4H+(aq)+4e−2H_2O(l) \rightarrow O_2(g) + 4H^+(aq) + 4e^-2H2O(l)→O2(g)+4H+(aq)+4e−
Anode material: Impure copper; half-equation: Cu2+(aq)+2e−→Cu(s)Cu^{2+}(aq) + 2e^- \rightarrow Cu(s)Cu2+(aq)+2e−→Cu(s)
Electrolytic processes Questions
Practise Edexcel GCSE Chemistry Electrolytic processes with exam-style questions for Foundation and Higher tier. 100 questions, matched to the Edexcel GCSE Chemistry (1CH0) specification and written in Paper 1 and Paper 2 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.