A-LevelChemistryElectrochemistryOct/Nov 2013Paper 1 Q31 Mark
The following half reactions occur when potassium iodate(V), KIO3, in hydrochloric acid solution oxidises iodine to ICl2⁻. IO3⁻ + 2Cl⁻ + 6H⁺ + 4e⁻ → ICl2⁻ + 3H2O I2 + 4Cl⁻ → 2ICl2⁻ + 2e⁻ What is the ratio of IO3⁻ to I2 in the balanced chemical equation for the overall reaction?
A1:1
B1:2
C1:4
D2:1
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The correct answer is B. This question tests the candidate's understanding of electrochemistry within the Chemistrysyllabus. The examiner's mark scheme requires...
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