Mass defect | definition of mass defect by Medical dictionary
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mass defect Chemistry
The difference in the mass of a polyatomic molecule and the sum of the masses of its constituent particles—i.e., electrons, protons and neutrons. The mass defect occurs because matter is converted into energy (as per Einstein’s E = mc2), which is the energy that binds the nucleus together and overcomes the mutual repulsion between protons.
In mass spectrometry, mass defect refers to the positive or negative difference between an ion’s exact mass and the nearest integer.
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References in periodicals archive
filters for XLR-11 utilized during data acquisition and data mining.
The term "mass defect" originates from the fact that only the carbon isotope--[sup.12]C--has an integer value for its atomic weight (12 or 12.0000 to be precise).
MMDF improves upon the MDF method by allowing the user to combine the results from up to six different mass defect filters.
(vi) [DELTA]E = A[c.sup.2][DELTA]m is useful in explaining the binding energy (2.2244MeV or 3.55904 x [10.sup.-13] J), mass defect
(0.002388 amu or 2.388 x [10.sup.-3] amu) and universal equality of mass of nucleons ([m.sub.n] = 1.008664 amu, [m.sub.p] = 1.006082 amu).