Sodium atoms and ions are monoisotopic, with a mass of about 23 u.
Chloride atoms and ions come in two isotopes with masses of approximately 35 u (at a natural abundance of about 75 percent) and approximately 37 u (at a natural abundance of about 25 percent).
The speed of a charged particle may be increased or decreased while passing through the electric field, and its direction may be altered by the magnetic field.
Goldstein called these positively charged anode rays "Kanalstrahlen"; the standard translation of this term into English is "canal rays".
Wilhelm Wien found that strong electric or magnetic fields deflected the canal rays and, in 1899, constructed a device with perpendicular electric and magnetic fields that separated the positive rays according to their charge-to-mass ratio (Q/m). Thomson later improved on the work of Wien by reducing the pressure to create the mass spectrograph.
The streams of sorted ions pass from the analyzer to the detector, which records the relative abundance of each ion type.
This information is used to determine the chemical element composition of the original sample (i.e.
Mass spectrometry is used in many different fields and is applied to pure samples as well as complex mixtures.