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Water - Solubility - Ions

Instrumental Methods - Mass Spectrometer.
Identifying Elements and Compounds.

A mass spectrometer can provide a quick and accurate
identification of a substance from a very small sample.

How does a Mass Spectrometer Work?

The instrument works by vapourising the sample (turning it into gas).
The sample passes through an electron beam which knocks off
some electrons from the molecules and turns them into ions.
The charged ions are accelerated towards a detector.
A strong magnetic field makes the ions follow a curved path
instead of moving in a straight line.
Ions with a small amount of mass curve the most
and ions with a large amount of mass curve the least.

Mass Spectrometer

A recorder draws a graph called a mass spectrograph
(usually just called a mass spectrum)
which shows a peak for each ion detected.
The position of the peaks show the mass to charge ratio
and this is used to identify the
substances which are present in the sample.

The mass to charge ratio is also used to
give the relative molecular mass (RMM or RFM)
of the substances in a sample.

A mass spectrometer is sometimes used
with gas chromatography to identify the
different compounds which leave the column.

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