Question

the difference between the actual isotopic mass and the sum of masses of proton neutron and electron is called

Answer 1

Answer:

Relative isotopic mass (a property of a single atom) is not to be confused with the averaged quantity atomic weight (see above), that is an average of values for many atoms in a given sample of a chemical element. While atomic mass is an absolute mass, relative isotopic mass is a dimensionless number with no units.

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Answer 2

The difference between the mass of the nucleus and the sum of each individual nucleon is called mass defect.

Thus, mass defect is the difference between the expected mass (calculated by adding the masses of protons, neutrons and electrons present) and the actual mass of an isotope.

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