molecular ion peak
What molecular ion peak means in Chemistry A-Level, as defined for AQA, OCR.
Definitions of molecular ion peak
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Reference: AQA
The peak at the highest mass to charge ratio, ignoring small isotope peaks beyond it, which gives the relative molecular mass directly.
The peak at the highest mass-to-charge value that is not an isotope satellite, formed when the whole molecule loses a single electron.
A small peak at the highest m/z value in the spectrum, whose m/z value equals the relative molecular mass of the compound.
The peak of the radical cation formed when the molecule loses one electron, giving the relative molecular mass.
The peak that gives the relative molecular mass of a separated component.
Topics that use molecular ion peak
- Chromatography (A-level only) (AQA A-Level)
- Mass number and isotopes (AQA A-Level)
- Mass spectrometry (AQA A-Level)
- Analytical techniques (OCR A-Level)
Related terms
- Absorption and re-emission of infrared radiation
- Absorption of infrared radiation
- Absorption of infrared radiation by bond vibrations
- abundance ratios
- acceleration to constant kinetic energy
- adsorption
- atomic number
- base peak
Using molecular ion peak in the exam
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