Chemistry A-Level
base peak
What base peak means in Chemistry A-Level, as defined for AQA, OCR.
Definitions of base peak
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Reference: AQA
The tallest peak, which is usually a fragment and must not be used to obtain relative molecular mass.
The most abundant ion, which is not necessarily the molecular ion.
Topics that use base peak
- Mass number and isotopes (AQA A-Level)
- Spectroscopy (OCR A-Level)
Related terms
- abundance ratios
- acceleration to constant kinetic energy
- atomic number
- Bond vibration and absorption of IR radiation
- Carbon environment
- Carbon-13 NMR and molecular symmetry
- Carbon-13 NMR prediction
- Carbon-13 NMR spectroscopy
Using base peak in the exam
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