abundant:
abundant Present in great quantity (the most abundant element is present in the largest amount)
Relative abundance (percent abundance, natural abundance):
Relative abundance ( percent abundance, natural abundance ) The amount of an isotope in a sample compared to the total amount of all isotopes in a sample
atomic mass (a.k.a. average atomic mass, weighted average atomic mass):
atomic mass (a.k.a. average atomic mass, weighted average atomic mass ) Weighted average mass of the atoms in a naturally occurring sample of the element Reflects both the mass and relative abundance (or percent abundance) of the isotopes as they occur in nature
atomic mass :
atomic mass “atomic mass” is also used to refer to the actual mass of a single atom: atomic mass of a neon-20 atom is 19.99 amu
Naturally occurring isotopes:
Naturally occurring isotopes The types (and amounts) of isotopes that occur in a natural sample of an element
Using average mass to determine the most abundant isotope::
Using average mass to determine the most abundant isotope: A naturally occurring sample of silicon contains Si-28, Si-29, and Si-30. The average atomic mass of silicon is 28.0855 u. Which isotope of silicon is the most abundant? Si-28 is most abundant, because the average mass is closer to 28 than to 29 or 30.