Mass Spectroscopy:

Mass spectroscopy is helpful in the analysis of an organic compound as it can give information about the molecular weight, the existence of speci?c elements (for example nitrogen, chlorine or bromine) and the existence of particular functional groups. Put at its simplest, a mass spectrum calculates the mass of ions, but to be more exact, it is a measure of the mass/charge ratio (m/e). Though, the huge majority of ions detected are singly charged (e=1). In order to acquire a mass spectrum, the molecules of the test compound have to be ionized within reduced pressure. There are various ways in which this can be carried out, but the most common technique is termed as electron ionization (EI).

Electron ionization includes bombarding the test molecule along with high-energy electrons such that the molecule loses an electron and ionizes to provide a radical cation called a molecular ion (as well called the parent ion). After that this molecular ion is accelerated through a magnetic ?eld towards a detector. The magnetic ?eld reasons the ion to deviate from a straight path and the extent of deviation is related to mass and charge (that is the lighter the ion the greater the deviation). Assuming a charge of 1, after that the deviation will be a measure of the mass. The mass can then be calculated to give the molecular weight.