Why is the atomic mass unit (amu) used to express the mass of subatomic particles and atoms instead of grams?
ChemistryClass 9CBSEAnswered 12 May 2026
Answer
The atomic mass unit (amu) is used because the masses of individual atoms and subatomic particles are extremely small when expressed in grams. Using amu provides more manageable and convenient numbers for calculations and comparisons at the atomic scale. 1 amu is defined as 1/12th the mass of a carbon-12 atom.
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