- Created by: Jenna190
- Created on: 10-09-19 18:13
What information does The Mass Spectrometer give?
It gives information about the relative atomic mass of an element and the relative abundance of its isotopes
What happens during Electrospray Ionisation?
The sample is dissolved into a solvent and pushed through a nozzle at a high pressure.
A high voltage is applied, causing each particle to gain a H+ ion.
The solvent is then removed leaving a gas of positive ions
What happens during Electron impact Ionisation?
The sample is vaporised and an 'electron gun' is used to fire high energy electrons at it.
This knocks off one electron from each particle, so they become ions with a +1 charge.
What happens during the acceleration stage?
The positive ions are accelerated by an electric field. It gives all ions the same kinetic energy.
Lighter ions experience greater acceleration as they are lighter.
What happens during the ion drift stage?
The ions enter a region with no electric field.
They enter at the same acceleration as before, so lighter ions travel faster.
What happens during the detection stage?
As lighter ions travel faster, they reach the detector faster.
It detects the current created when the ions hit the detector and records how long it took to pass through the Spectrometer.
The data calculates the mass/charge values needed to produce a mass spectrum (a type of graph used for spectrometers)
What are the stages in order?
- 1.) Ionisation - either electrospray or electron impact ionisation
- 2.) Acceleration
- 3.) Ion drift
- 4.) Detection