Chemistry A-Level
precise atomic masses
What precise atomic masses means in Chemistry A-Level, as defined for AQA.
Definition of precise atomic masses
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Reference: AQA
The masses given in the question for individual isotopes, used instead of the weighted average relative atomic mass in the periodic table.
Topics that use precise atomic masses
- Mass spectrometry (AQA A-Level)
Related terms
- comparison to several decimal places
- high resolution
- isomers not distinguished
- molecular ion peak
- candidate formulae
- rejecting alternatives
Using precise atomic masses in the exam
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