Explain5 marksChallenge
The carbon-13 NMR spectrum of benzene, , shows only one peak, at about 128 ppm.
Explain why the spectrum of benzene shows only one peak.
CAIE A Level Chemistry 9701 · Analytical techniques
Analytical techniques: explain question
How this question is marked
5 marks, so the mark scheme is looking for about 5 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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