F321

Isotope – atoms of the same element with different numbers of neutrons and therefore a different mass.

Relative Molecular Mass – the weighted mean mass of a molecule relative to one twelfth of the mass of a carbon 12 atom.

Relative formula mass – the weighted mean mass of a formula unit compared with one twelfth of the mass of an atom of carbon 12.

Relative Atomic Mass – the weighted mean mass of an atom of an element relative…