How is the mass number of an atom calculated based on its subatomic particles?

A.VERIFIED ANSWERfact-checked by tutors

The mass number is calculated by adding the total number of protons and neutrons in the atom's nucleus.

The mass number (A) represents the total number of nucleons (protons and neutrons) in an atom's nucleus. Since electrons have negligible mass compared to protons and neutrons, they are not included in the mass number calculation. This number gives an approximation of the atom's atomic mass.

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