Mass Spectrometers

Mass spectrometers, is an equipment that convert molecules into ions and then separates th ions according to their mass-to-charge ratio. Althought many diffirent kinds of mass spectrometer are us today, they are all relate to a device developed by the British physicist Fancis William Aston in 1919. In his spectrometr; a thin beam of positivly charge ions was first deflected by an electric field and then deflected in the opposite direction by a magnetic field. The amount of deflection of the particles as registered on a photographis plate depend on their mass and velocity: the greater the mass or velocity of the ions, the less it was deflects. Aston measured the molecular weights of the isotopes of many elements as well as the elative abundance of these isotopes in nature.

Common of

mass spectrometer

All of the mass spectrometer shares fur features in common:

a system for introducing the substance to be analyzed into the instruments.

an system for ionizing the substance

an accelerator that directs he ions into the measuring apparatus.

a system for separating the constituent ions and recording the mass spectrum of the substance.

Uses of

Mass Spectrometer

Mass spectrometer are use to identify atoms and isotopes and determine the chemical composition of a sample. mass spectrometers can provide a high degree of resolution to ai in th analusis of complex mixtures. For example, products of petroleum refiing and processing, which usually contain various closely relate hydrocarbons, are difficult to separateby convetional methods of chemical analysis, but can be isolate ans analuzed using a mass spectrometer. A tandem mass spectrometer, which consists of multiplemass spectrometer makes it possible to establish the linear sequence of amino acids in a protein molecule in a matter of minutes. These mass spectrometers are more than thousand times sensitive than any single unit, making them useful for analyzing extremly small quantities of biological compouds with large molecular weights. The most sensitve devices that can be use as mass spectrometer are tandem electrostatic accelerators, which comprise series of cinventional mass spectrometers connected to a powerful electrostatic praticle accelerator. These devices can separate atoms or small molecules that have masses thatdiffer by 1 part in 100,000 or less.