Study Set Content:
the sample molecules are subjected to a high energy beam of electrons, converting some of them to ions
Creation of ions
as they are accelerated in an electric field, the ions are separated according to mass-to-charge ratio (m/z)
Separation of ions–
as each separated population of ions is generated, the spectrometer needs to qualify and quantify them
Detection of ions
The differences in mass spectrometer types are in the different means to carry out these
three functions
Common to all is the need for ____ (~ 10-6torr), while still allowing the introduction of the sample
very high vacuum
PRINCIPLE
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Charged molecules or molecular fragments are generated in a____ or immediately prior to a sample entering a high-vacuum region, using a variety of methods for ion production. The ions are generated in the () so that they can then be manipulated by the application of either electric or magnetic fields to enable the determination of their molecular weights.
high-vacuum region,gas phase
The principle involved in mass spectrometry is the formation of ____ from the sample
several ions
Further, these ions are separated according to their mass to charge ratio, which is also expressed as m/z and then taking a record of the ____ of each ion.
relative abundance
plot of relative abundance against the mass/charge ratio (m/e) is called a
mass spectrum
THREE MAIN COMPONENTS OF MASS SPECTROMETER
1) Ion source
2) Analyzer
3) Detector system
referred to as the heart of the spectrometer. This is where either an
electron is removed or a proton is added, giving the molecule a positive
charge. Molecules are ionized/converted into gas-phase ions so that they
can be moved and manipulated by external electric and magnetic fields.
Ion source
There are a variety of mass analyzers available, and they work with the ion detection system. Mass analyzers will vary in their operational
requirements such as operating speed and separation resolution.
Analyzer
will detect the separated ions by recording the charge of ions passing through the surface and quantify them.
Detector system
