Design and Operation of a Portable Quadrupole Mass Spectrometer for the Undergraduate Curriculum

We describe the design and construction of a teaching mass spectrometer from components that are available commercially. The instrument is transportable, robust, and inexpensive. It yields a mass spectrum 3 minutes after being switched on and is designed to be used by undergraduates and maintained by faculty without special instrumental skills.Several experiments are described, ranging from atomic weight determination (first year) to molecular effusion (junior year). Emphasis is placed on the use of the instrument for routine chemical analysis throughout the undergraduate curriculum.