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Isotopes of Magnesium (click to see decay chain): 19Mg  20Mg  21Mg  22Mg  23Mg  24Mg  25Mg  26Mg  27Mg  28Mg  29Mg  30Mg  31Mg  32Mg  33Mg  34Mg  35Mg  36Mg  37Mg  38Mg  39Mg  40Mg

21Mg     Half-life Fermion, 12p 9n 122 ms Spin 5/2 Parity 1 Show Decay Modes Hide Ultimate Decay Products Yield Nuclide 67% 21Ne 32.6% 20Ne 0.5% 17O Atomic Weight 21.01171291 Abundance None Mass Excess 10.910506MeV Binding Energy 7.104714MeV Magnetic Moment N/A Quadrupole Moment N/A   Show Isotope Symbols. Also show decay chains leading to this isotope. Show all decays, even very low-probability. Show Decay Image Smaller.

Click any isotope in diagram to see its data. Decay chain image generated by Mathematica's GraphPlot and IsotopeData functions from Wolfram Research, Inc..