QCEVault

Chemical synthesis — Question 57

Original QCE Vault practice · 5 marks

Q57 · Practice questionComplex familiar5 marks

QUESTION 57 (5 marks)

A hydrogen–oxygen fuel cell operates in alkaline electrolyte.

a) Write the anode and cathode half-equations, using four electrons in each. [3 marks]

b) Show the overall equation after cancelling species. [1 marks]

c) Explain why the fuel cell can continue delivering current for longer than a sealed galvanic cell containing a fixed amount of reactants. [1 marks]

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