Qualitative mass spectrometry focuses on identifying the chemical structure and composition of compounds in a sample. The uniqueness of MS is due to the fact that it enables direct identification of molecules based on the mass-to-charge ratios as well as fragmentation patterns. Thus, for several decades now, MS has been used in qualitative chemical analysis. To address the pressing need for quantitative molecular. Mass spectrometry (MS) is the only instrumental analytical technology that utilizes unique properties of matter, that is, its mass (m) and electrical charge (z). This guide will explain how they work and their many uses.