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Mass number and isotopes



Atomic Structure

AQA Content

determine the number of fundamental particles in atoms and ions using mass number, atomic number and charge
explain the existence of isotopes.
interpret simple mass spectra of elements
calculate relative atomic mass from isotopic abundance, limited to mononuclear ions.

Specification Notes

Mass number (A) and atomic (proton) number (Z).

The principles of a simple time of flight (TOF) mass spectrometer, limited to ionisation, acceleration to give all ions constant kinetic energy, ion drift, ion detection, data analysis.
The mass spectrometer gives accurate information about relative isotopic mass and also about the relative abundance of isotopes.
Mass spectrometry can be used to identify elements.
Mass spectrometry can be used to determine relative molecular mass.



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