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AP Chemistry
The average mass is a calculated value obtained by multiplying each isotope's mass by its abundance and summing these values. It represents the weighted average mass of all isotopes present in a sample.
Atoms of the same element that have different numbers of neutrons.
Abundance: The relative amount or proportion of an isotope compared to others in a sample.
Atomic mass unit (amu): A unit used to express atomic and molecular weights, which is equal to one-twelfth the mass of a carbon-12 atom.