Question

What is weighted average in chemistry?

Answer 1

The atomic weights of elements shown in the periodic table are weighted averages of the various isotopes. That means that if element X has a mass of 60 and it is 60% abundant and an isotope of mass 61 is 40% abundant, then the mass shown in the periodic table is averaged at 0.60(60) + 0.40(61) = 60.4
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