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Consider the following reactions: 2C + O2 → 2CO2; ΔH = −0393 J 2Zn + O2 → 2ZnO; ΔH = −412 J Which statement is supported by these reactions?

1. Carbon is able to oxidise zinc
2. Carbon cannot undergo oxidation
3. Zinc cannot be oxidised
4. Zinc is able to oxidise carbon

Correct answer: Carbon is able to oxidise zinc

Solution

The reactions show that carbon can react with oxygen to form carbon dioxide, releasing energy, while zinc also reacts with oxygen to form zinc oxide. Since both reactions are exothermic, and carbon is capable of oxidizing zinc, it indicates that carbon can indeed oxidize zinc.

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