A-LevelChemistryElectrochemistry9701/12 · Oct/Nov 2019 · Q81 Mark

(NH₄)₂Cr₂O₇ decomposes when heated. (NH₄)₂Cr₂O₇ → N₂ + 4H₂O + Cr₂O₃ Which element is oxidised and which element is reduced?

Aoxidised: chromium, reduced: nitrogen

Boxidised: hydrogen, reduced: chromium

Coxidised: nitrogen, reduced: chromium

Doxidised: nitrogen, reduced: hydrogen

✓ Correct answer

C: oxidised: nitrogen, reduced: chromium

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Topic: Electrochemistry, A-Level Chemistry (syllabus 9701). Multiple choice, 1 mark.
Source: A-Level Chemistry, Oct/Nov 2019 Paper 1 Variant 2, question 8.

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