Name and explain briefly the main stages of mass spectroscopy.

Mass spectroscopy is a highly sensitive method of analysing samples of elements and determining the isotopes present and their relative amounts. We can break down the method into four major steps: (in order)Ionisation: After the sample is vaporised, high-energy electrons are fired at the sample by an electron gun, knocking off an outer shell electron to form a positive ion.Acceleration: These positive ions are passed through an electric field and therefore focused into a narrow beam of ions.Deflection: The positive ions have high kinetic energy so move fast and are deflected by a strong magnetic field; the heavier the ion, the less it is deflected by the magnet. The degree of deflection also depends on the number of positive charges on the ion - although most ions have a single positive charge since it is more difficult to remove an electron from an already positively charged ion, some ions may lose multiple electrons - and, the higher the positive charge, the more the ion is deflected.Detection: The beam of positive ions is detected electronically and a mass spectrum is produced.

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