Author Question: True or false, both mass spectrometry and infrared spectroscopy involve the interaction of molecules ... (Read 117 times)

vicky · **on:** Aug 23, 2018

True or false, both mass spectrometry and infrared spectroscopy involve the interaction of molecules with electromagnetic energy?
Indicate whether the statement is true or false

Question 2

Could you distinguish 2,2-dimethylbutane from 2-methylpentane using mass spectrometry?

hollysheppard095 · **Reply #1 on:** Aug 23, 2018

Answer to Question 1

FALSE

Answer to Question 2

Yes, although M+ at m/z = 86 for both compounds is identical, the fragmentation patterns of the two compounds should show two major differences. We would expect 2,2-dimethylbutane to have significant peaks at m/z = 57, corresponding to C4H9, and m/z = 71, corresponding to C5H11 . Fragmentation of 2-methylpentane should produce significant peaks at m/z = 43, corresponding to C3H7, and m/z = 57, corresponding to C4H9.