CAIE A Level Chemistry 9701 · Analytical techniques
The mass spectrum of a bromoalkane shows a molecular ion peak at m/e = 122 and a peak of similar height at m/e = 124. The spectrum also shows a fragmentation peak at m/e = 43.
Compare the information given by the peaks at m/e = 122 and m/e = 124 with the information given by the peak at m/e = 43.
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.
Compare means: Give similarities or differences between two things, and say which side each point belongs to. Write each point as a pair, for example: A is X, whereas B is Y. Two separate descriptions rarely earn the marks.
Written by Markquill to follow the Cambridge International syllabus. Markquill is independent and is not affiliated with or endorsed by Cambridge International.