What m/z ratio would expect to find in the mass spectrum of the following compound due to dehydration?
A)102
B)87
C)85
D)84
E)59

Question

What m/z ratio would expect to find in the mass spectrum of the following compound due to dehydration? 
A)102 
B)87 
C)85 
D)84 
E)59

Quizplus · Accepted Answer

Dehydration typically results in the loss of a water molecule with a mass of 18 amu. Therefore, we would expect to see a peak in the mass spectrum that is 18 amu less than the molecular ion peak. The molecular ion peak in the provided spectrum is at m/z 102, so we would expect the dehydrated peak to be at 84 amu (102 - 18). Choice D is the only option that matches this expected peak.

What M/z Ratio Would Expect to Find in the Mass