mass spectrometry

mass spectrometry

 or mass spectroscopy

Analytic technique by which chemical substances are identified by sorting gaseous ions by mass using electric and magnetic fields. A mass spectrometer uses electrical means to detect the sorted ions, while a mass spectrograph uses photographic or other nonelectrical means; either device is a mass spectroscope. The process is widely used to measure masses and relative abundances of different isotopes, to analyze products of a separation by liquid or gas chromatography, to test vacuum integrity in high-vacuum equipment, and to measure the geological age of minerals.

---

mass spectrometry [′mas spek′träm·ə·trē]

(analytical chemistry)

An analytical technique for identification of chemical structures, determination of mixtures, and quantitative elemental analysis, based on application of the mass spectrometer.