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A level Mass Spectrum Diagrams

In my A-Level course we don't need to know much about fragmentation, but how do I tell from a mass spectrum diagram which lines are due to the molecular ion being broken down into smaller fragments?

Reply 1

charco

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Original post by NaBrO

In my A-Level course we don't need to know much about fragmentation, but how do I tell from a mass spectrum diagram which lines are due to the molecular ion being broken down into smaller fragments?

If you are dealing with a compound, all lines below the molecular ion m/z values will be due to fragments.
If you are dealing with a diatomic molecule yo will also have (m/z)/2 values due to atomic fragments.
However, chlorinated and brominated compounds will have more than one molecular ion due to isotopes.