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6 Cards in this Set
- Front
- Back
- 3rd side (hint)
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Stage 1: Ionisation - Electrospray Ionisation |
-Sample is dissolved in a solvent -Injected through a needle at high voltage -Gains a proton |
Solvent, Needle & Proton |
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Stage 1: Ionisation - Electron Impact (Electron Gun) |
-High energy electrons from an electron gun -Fired at the sample and knock off an electron |
The Lion King |
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Stage 2: Acceleration |
-The positive ions are accelerated by an electric field to a constant kinetic energy -The rate at which they are accelerated is dependent on their masses -Ions with a lower mass will travel faster and will have a higher velocity -Ions with a higher mass will travel slower and will have a lower velocity |
Electric Field, Kinetic Energy, Mass & Velocity |
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Stage 3: Ion Drift |
-Ions will separate (All Ions have a constant kinetic energy) -Ions are allowed to drift in a flight tube and the time it takes for the Ions to reach a detector at a known distance in measured -This time will depend on the mass of the ion -Lighter Ions reach higher velocities, therefore Ions with a low mass will reach the detector first and those with a high mass will arrive last -The mass of the Ion can be determined from the time taken for the Ion to reach the detector |
Separate, Time, Distance, Mass & Velocity |
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Stage 4: Ion Detection |
-Positive Ions hoy the detector (a negatively charged plate) and pick up electrons -A current is generated when the Ions gain an electron -The greater the abundance of the Ions hitting the detector, the bigger the current produced |
Detector, Current & Abundance |
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Stage 5: Data Analysis |
-The detector is linked to an amplifier and recorder, which converts the current into a peak and that is shown in a mass spectrum -The height of the peak is proportional to the size of the current generated and therefore proportional to the abundance of the Ion -Flight times are analysed and recorded as a plot of abundance v mass/charge ratio or m/z |
Peak, Height, Current and Ratio |
