Q1. [2] medium thorough-understanding
In the reaction ZnO + C → Zn + CO, identify the oxidising agent and the reducing agent. Explain your answer in terms of the gain and loss of oxygen by each substance.
Generated by claude-sonnet-4-6 · 2026-06-26 00:55 · grounding rag
Model Answer
In ZnO + C → Zn + CO:
- ZnO is the oxidising agent — it gives oxygen to carbon, thereby getting reduced (loses oxygen to form Zn).
- C is the reducing agent — it gains oxygen from ZnO to form CO, thereby getting oxidised.
Oxidation = gain of oxygen; Reduction = loss of oxygen.
Source: Chapter 1, "What you have learnt"
Explanation
- Examiners award 1 mark for correctly identifying both agents and 1 mark for the explanation in terms of gain/loss of oxygen.
- A common mistake is confusing the two: always link "oxidising agent" to the substance that provides oxygen (and itself gets reduced), and "reducing agent" to the substance that takes oxygen (and itself gets oxidised).
- Stating the definitions of oxidation and reduction in the last line shows conceptual clarity and helps secure full marks.