CAIE A Level Chemistry 9701 · Analytical techniques
The mass spectrum of butane, , shows a molecular ion peak at . The two most abundant fragment peaks are at and .
Describe what the molecular ion peak tells you about the molecule, and suggest the identities of the fragments responsible for the peaks at and .
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.
Describe means: Say what happens or what something is like, in order and with detail. You are not being asked why. If there is data, quote it: name the trend, then give figures with units at the points where it changes.
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