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Question
Explain the need of the term average atomic mass.
Solution
- Several naturally occurring elements exist as a mixture of two or more isotopes.
- Isotopes have different atomic masses.
- The atomic mass of such an element is the average of atomic masses of its isotopes.
- For this purpose, the atomic masses of isotopes and their relative percentage abundances are considered.
Hence, the term average atomic mass is needed to express the atomic mass of elements containing a mixture of two or more isotopes.
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