The Mass Spectrometer

The mass spectrometer is a device used to study isotopes of ions produced in a cathode ray
tube. Isotopes of an element share the same chemical properties but have different masses and produce different values for their charge-to-mass ratio. An electron beam strikes vapor atoms that yield positive ions accelerated by a potential difference and deflected by a uniform magnetic field to hit a photographic plate. Mass spectrometry can also be used to identify molecules by analyzing the masses of its fragments.

SNAPSHOTS

  • [Snapshot]
  • [Snapshot]
  • [Snapshot]

DETAILS

The charge-to-mass ratio of an ion can be derived from Newton's second law and the Lorenz force, yielding
,
where is the charge, is the mass, is the potential difference, is the magnetic field intensity, and is the radius of gyration.
    • Share:

Embed Interactive Demonstration New!

Just copy and paste this snippet of JavaScript code into your website or blog to put the live Demonstration on your site. More details »

Files require Wolfram CDF Player or Mathematica.