mass defect


Definition of mass defect

: the difference between the mass of an isotope and its mass number expressed in atomic mass units and being either positive or negative the mass defect of the carbon isotope6C12, mass 12.00388, is +0.00388, while that of phosphorus15P31, isotopic mass 30.984, is −0.016 — compare binding energy, packing fraction

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Cite this Entry

“Mass defect.” Dictionary, Merriam-Webster, Accessed 29 Oct. 2020.

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