mass defect

noun

: 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.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/mass%20defect. Accessed 20 Jun. 2024.

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