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Redox and electrochemistry — Question 97

Original QCE Vault practice · 7 marks

Q97 · Practice questionComplex unfamiliar7 marks

QUESTION 97 (7 marks)

A zinc–copper galvanic cell contains 50.0 mL of 0.100 mol L⁻¹ Cu²⁺ solution and excess zinc. In an ideal model, Cu²⁺ reduction is the only cathode reaction. The cell supplies a constant 0.200 A until all initial Cu²⁺ is consumed. Use F=96485 Cmol−1, M(Cu)=63.55 and M(Zn)=65.40 gmol−1.

a) Write the net ionic reaction. [1 marks]

b) Calculate the maximum copper mass gain and zinc mass loss. [3 marks]

c) Calculate the operating time in minutes. [2 marks]

d) Explain why the constant-current assumption becomes less realistic near depletion. [1 marks]

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