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applications of chemistry - Coggle Diagram
applications of chemistry
ionisation
Ionisation: atoms or molecules that are ionised by producing 1 or more electrons give a positive ion.
mass spectrometry
Mass spectrometry is an analytical method used to determine the identity of an organic compound.
A mass spectrometer (the apparatus used for mass spectrometry) consists of an ionisation chamber, an electric and magnetic field, an ion collector and a detector connected to a database
The process of mass spectrometry begins at the ionisation chamber in which a sample of the volatile organic compound is ionised being bombarded with high velocity electrons
This causes the sample to break up into fragment ions with specific mass to charge (m/z) ratios
limitations
Must be used in conjunction with other analytical techniques like IR spectroscopy and nuclear magnetic resonance spectroscopy
Can't distinguish between structural isomers
mass spectrum
On a mass spectrum, peaks are plotted as abundance measured by a relative intensity
The peak with the highest m/z ratio is usually denoted as the molecular ion peak
m/z
An electron is taken away from molecules to create single charged ions. If there happens to be two electrons removed, double charged ions are produced.
Z stands for the charge number of ions
M stands for mass
m/z= mass to charge ratio
advantages
advantages
Highly sensitive (producing highly precise results)
Determines isotopic abundance
Spectral elucidation (determining the identity of the organic compound if there is a database available)
Can determine molar mass and relative elemental abundance of a sample easily
alkanes
In alkanes, the C-C bonds are weaker than the C-H bonds. Ionisation of the molecule results in greatly reduced bond strengths.
alkane- molecular ions peaks are present, with low intensity. The fragmentation pattern contains peaks 14 mass units’ part
carboxylics
Carboxylic acid- short chain acids, peaks due to the loss of OH- ions
mass analyser
a mass analyser is the component of the mass spectrometer that takes ionized masses and seperates them based on charge to mass ratios and outputs them to the detector where they are detected and later converted to a digital output
