H Home Background Color: He Li Be Radium Main Page Black White Gray B C N O F Ne Na Mg Radium Pictures Page Al Si P S Cl Ar K Ca Radium Technical Data Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe Cs Ba La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn Fr Ra Ac Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr Rf Db Sg Bh Hs Mt Ds Rg Cn Nh Fl Mc Lv Ts Og

Isotopes of Radium (click to see decay chain): 202Ra  203Ra  204Ra  205Ra  206Ra  207Ra  208Ra  209Ra  210Ra  211Ra  212Ra  213Ra  214Ra  215Ra  216Ra  217Ra  218Ra  219Ra  220Ra  221Ra  222Ra  223Ra  224Ra  225Ra  226Ra  227Ra  228Ra  229Ra  230Ra  231Ra  232Ra  233Ra  234Ra

221Ra     Half-life Fermion, 88p 133n 28 s Spin 5/2 Parity 1 Hide Decay Modes Probability Mode Decay Energy Daughter 100% α 6.88039MeV 217Rn 1.2×10-10% 14C N/A 207Pb Show Ultimate Decay Products Atomic Weight 221.013917338 Abundance None Mass Excess 12.963917MeV Binding Energy 7.701134MeV Magnetic Moment -0.1799 μ Quadrupole Moment 1.978   Show Isotope Symbols. Show only decay products of this isotope. 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..