A mass spectrum is an intensity versus m/z (mass-to-charge ratio) plot that represents a chemical analysis. The mass spectrum of a sample is a pattern representing the distribution of ions by mass (more correctly: mass-to-charge ratio) in a sample. It is a histogram usually made using an instrument called a mass spectrometer. Not all mass spectra of a given substance are the same. It can depend on the operating conditions of the instrument. For example, some mass spectrometers break the analyte molecules into many pieces; others observe the intact molecular masses with little fragmentation. A mass spectrum can represent many different types of information based on the type of mass spectrometer and the specific experiment; however, all plots of intensity vs. mass-to-charge are called "mass spectra".
- NIST toluene spectrum.
- International Union of Pure and Applied Chemistry. "mass spectrum". Compendium of Chemical Terminology Internet edition.
- Interactive tutorial on mass spectra National High Magnetic Field Laboratory
- Weighing Atoms: A layperson's introduction to mass spectrometry National High Magnetic Field Laboratory
- What's in an Oil Drop: A layperson's introduction to Fourier Transform Ion Cyclotron Resonance National High Magnetic Field Laboratory
- Quantities, Units and Symbols in Physical Chemistry (IUPAC green book)
- An introductory video on Mass Spectrometry The Royal Society of Chemistry