Question

How is mass spectrometry used in the analysis of hydrocarbons?

Answer 1

Have you not got a text?

Explanation:

Take hexanes, or octanes; put it in a mass spectrometer and we would LIKE to see a peak at `86` and `114` `"amu"`...whether we see the molecular ion or not is a function of the experimental conditions. Of course, the parent ion is going to fragment, and give characteristic daughter peaks....

For volatile compounds, i.e. for MOST organic compounds, solid or liquid at room temperature and pressure, we are very likely to see the molecular ion in the standard experiment.