ABSTRACT
The interpretation of a mass spectrum cannot be improvised: experience shows that chemists who are not properly trained in mass spectrometry are often embarrassed when they start tackling the interpretation of mass spectra. This is because the chemistry of ions in the gaseous phase is often different from the chemistry of the same ions in solution. Most chemists learned to deal with solutions using techniques such as pH metrics, titration, and synthesis. Furthermore, except for photochemistry, classical training treats species with even numbers of electrons: molecules and MH+ or [M-H]– ions, respectively, emitted from protonated or deprotonated molecules.
