Which of the following is expected to be the base peak in the mass spectrum of pentanal?

Question

Quizplus · Accepted Answer

The base peak in a mass spectrum represents the most stable and abundant ion produced. In pentanal, the most stable and abundant fragment ion is expected to be the one resulting from the loss of a methyl group (CH3) from the molecular ion (M), which has a mass of 86. The resulting ion has a mass of 44, which is the same as the molecular ion of carbon dioxide (CO2), a very stable and common fragment in mass spectra. Therefore, the base peak in the mass spectrum of pentanal is expected to be at m/z 44.

Which of the Following Is Expected to Be the Base