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If a mass spectrometer reading indicates a signal at 80 amu and a signal roughly three times larger at 78 amu, then that the organic molecule likely contains:
A. a bromine atom
B. a chlorine atom
C. an amine group
D. an ester group
The mass spectrometer results for bromine would would show 2 peaks of roughly equal size separated by 2 amu while chlorine would 2 peaks in a 3:1 ratio separated by 2 amu. In the answer explanation they state that neither amine group nor an ester group would cause 2 signals 2 amu apart from one another and the ratio of the signals produced could not be 3:1. Where did they get this information from? Had I not just read a paragraph explaining the 1:1 and 3:1 ratios for bromine and chlorine I would not have been able to get this. Doesn't this require knowledge of how the radical cations would fragment?
From the AAMC Biological Sciences Content Outline:
It does not seem necessary to know anything about fragmentation. TBR shows the mass spectroscopy graph for butanone and they list 4 peaks of interest one of which is the parent peak and another is the base peak. Why the other two peak values are given is not explained. I know it has to do with the fragmentation.
Can someone explain what the Y-axis means in a mass spectrometry graph?
The peak at 44 m/z is 100. TBR lists the Y-axis as being relative intensity. What do we mean when we say that the peak at 44 m/z has a relative intensity of 100? How is the intensity measured? I know that mass spectrometry is used to measure the mass of organic compounds and that the charge on most of the cations is +1, which allows us to say that m/z is the mass of the compound. When looking at the graph is the peak at 44 amu both the parent peak (M+) and the base peak?
A. a bromine atom
B. a chlorine atom
C. an amine group
D. an ester group
The mass spectrometer results for bromine would would show 2 peaks of roughly equal size separated by 2 amu while chlorine would 2 peaks in a 3:1 ratio separated by 2 amu. In the answer explanation they state that neither amine group nor an ester group would cause 2 signals 2 amu apart from one another and the ratio of the signals produced could not be 3:1. Where did they get this information from? Had I not just read a paragraph explaining the 1:1 and 3:1 ratios for bromine and chlorine I would not have been able to get this. Doesn't this require knowledge of how the radical cations would fragment?
From the AAMC Biological Sciences Content Outline:
It does not seem necessary to know anything about fragmentation. TBR shows the mass spectroscopy graph for butanone and they list 4 peaks of interest one of which is the parent peak and another is the base peak. Why the other two peak values are given is not explained. I know it has to do with the fragmentation.
Can someone explain what the Y-axis means in a mass spectrometry graph?
The peak at 44 m/z is 100. TBR lists the Y-axis as being relative intensity. What do we mean when we say that the peak at 44 m/z has a relative intensity of 100? How is the intensity measured? I know that mass spectrometry is used to measure the mass of organic compounds and that the charge on most of the cations is +1, which allows us to say that m/z is the mass of the compound. When looking at the graph is the peak at 44 amu both the parent peak (M+) and the base peak?
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