Ethanol can be oxidised by heating with potassium dichromate(VI) in dilute sulfuric acid
3 marks · EasyDescribe the observable change in colour that occurs when ethanol is oxidised by heating with potassium dichromate(VI) in dilute sulfuric acid.
What does this colour change indicate about the potassium dichromate(VI) during the reaction?
Suggest what you would observe if the solution is heated without adding ethanol.
Work this out on paper, then compare with the answer and worked solution below. With a free account you can submit written answers for marking.
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(a) The solution changes from orange to green. · must show orange to green
(b) It indicates that potassium dichromate(VI) is reduced. · must show reduction of potassium dichromate(VI)
(c) No colour change—the solution stays orange. · must show no colour change
Show mark scheme and worked solution
Marking points
B1 (a) · 1 mark · Describes the colour change as orange to green.
B2 (b) · 1 mark · States that the potassium dichromate(VI) is reduced.
B3 (c) · 1 mark · States that with no ethanol, there is no colour change; solution remains orange.
Worked solution
a) The solution changes from orange to green.
b) This means potassium dichromate(VI) is reduced during the reaction.
c) If no ethanol is added, there is no colour change and the solution remains orange.