Explain4 marksStandard
A student electrolyses dilute aqueous sodium chloride using inert carbon electrodes. The products at the electrodes are hydrogen and oxygen.
Explain why these products are formed rather than sodium and chlorine.
CAIE A Level Chemistry 9701 · Electrochemistry
Electrochemistry: explain question
How this question is marked
4 marks, so the mark scheme is looking for about 4 separate creditworthy points. Making the same point twice in different words earns it once.
Explain means: Give the reasons or the mechanism: why or how something happens. Link each point to the next with because, so or which means. A list of facts with no links usually loses the reasoning marks.
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