Displacement reactions involving solutions of salts
2 marks · EasyIn the reaction:
State which substance acts as the oxidising agent and which acts as the reducing agent. Explain your answer in terms of electron transfer.
Work this out on paper, then compare with the answer and worked solution below. With a free account you can submit written answers for marking.
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Pb^{2+} is the oxidising agent and Zn is the reducing agent. The oxidising agent gains electrons (Pb^{2+} is reduced) and the reducing agent loses electrons (Zn is oxidised).
Also accept: Zinc is the reducing agent because it loses electrons; lead(II) ion is the oxidising agent because it gains electrons.
Common mistakes: Mixing up agents or electron flow
Show mark scheme and worked solution
Marking points
B1 · 1 mark · States Pb^{2+} is the oxidising agent and Zn is the reducing agent (or equivalent).
B2 · 1 mark · Explains in terms of electron transfer: oxidising agent gains electrons/reducing agent loses electrons.
Worked solution
Pb^{2+} acts as the oxidising agent because it accepts electrons from Zn. Zn acts as the reducing agent because it loses electrons to Pb^{2+}. The oxidising agent gains electrons and is reduced, the reducing agent loses electrons and is oxidised.