Mass Spectroscopy of Elements

Mass spectroscopy is a technique used to determine the mass-to-charge ratio of ions. It can also be used to find out the relative atomic mass of an element and to identify isotopes.
Ions are created in the mass spectrometer by removing one or more electrons to give a positive charge.
The basic principles behind it involve ionising a sample of the element and causing it to move in a magnetic field. The speed and path of the ions will vary depending on their mass and charge.

The process usually begins with vaporisation, where the sample to be tested is turned into gas.
Then it passes through the ionisation chamber, where high energy electrons remove an electron from the atom, creating a positive ion.
The positive ions are then accelerated through an electric field. Lighter and more charged ions will be deflected more than heavier or less charged ones when they enter the magnetic field.
These resulting ions are then detected on a screen producing a mass spectrum, which reflects the masses and relative concentrations of the sample’s ions.

The results of a mass spectrometer are displayed as a mass spectrum. The mass spectrum gives the relative abundance of each ion type.
The position of each peak on the horizontal axis gives the mass-to-charge ratio. The height or intensity of each peak gives the relative abundance of each ion.
The relative atomic mass of an element can be determined from the mass spectrum, by taking the average of the isotopic masses, weighted by their relative abundances.
Isotopes of an element can also be identified using a mass spectrum as they each have a unique mass-to-charge ratio, so will each have a different position on the spectrum.

Mass spectrometry has applications in many fields, including medicine, forensic science and environmental science. It can be used to: identify unknown compounds, quantify known compounds, and determine structure and chemical properties of molecules.
In pharmaceutical research, it is used for drug discovery and development, and in the clinical laboratory for assessing patient health.
In space exploration, mass spectrometers have been used on spacecraft for remote sensing of planets and moons by analysing the composition of their atmospheres or surfaces.