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O-LevelChemistryMetals & Reactivity5070/11 · May/June 2019 · Q201 Mark

Gas X turns acidified potassium manganate(VII) from purple to colourless. Gas Y turns aqueous potassium iodide from colourless to brown. What do these observations show about gas X and gas Y?

Agas X: oxidising agent, gas Y: oxidising agent
Bgas X: oxidising agent, gas Y: reducing agent
Cgas X: reducing agent, gas Y: oxidising agent
Dgas X: reducing agent, gas Y: reducing agent

✓ Correct answer

C: gas X: reducing agent, gas Y: oxidising agent

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About this question

Topic
Metals & Reactivity, O-Level Chemistry (syllabus 5070). Multiple choice, 1 mark.
Source
O-Level Chemistry, May/June 2019 Paper 1 Variant 1, question 20.

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