Explain why the mass number is always a whole number, even though atomic masses often have decimal values.
ChemistryClass 11CBSEAnswered 18 May 2026
Answer
The mass number represents the count of whole protons and neutrons in a single atom's nucleus, which are discrete particles. Atomic masses, however, are weighted averages of the masses of all naturally occurring isotopes of an element, which often results in decimal values.
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