Per NCERT, what is the AVERAGE ATOMIC MASS of an element — and why is it used?
AWeighted average of the atomic masses of an element's NATURAL ISOTOPES (weighted by relative abundance)
BSimple arithmetic mean of all isotopes
CMass of the lightest isotope only
DAlways the mass of the most common isotope
Answer & Solution
Correct answer: A. Weighted average of the atomic masses of an element's NATURAL ISOTOPES (weighted by relative abundance)
Per NCERT §1.7.2, average atomic mass = sum of (abundance × isotope mass). Reflects natural isotopic composition.
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