H Home Background Color: He Li Be Protactinium Main Page Black White Gray B C N O F Ne Na Mg Protactinium Pictures Page Al Si P S Cl Ar K Ca Protactinium 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 Protactinium (click to see decay chain): 212Pa  213Pa  214Pa  215Pa  216Pa  217Pa  218Pa  219Pa  220Pa  221Pa  222Pa  223Pa  224Pa  225Pa  226Pa  227Pa  228Pa  229Pa  230Pa  231Pa  232Pa  233Pa  234Pa  235Pa  236Pa  237Pa  238Pa  239Pa  240Pa

221Pa     Half-life Boson, 91p 130n 5.9 µs Spin 9/2 Parity -1 Hide Decay Modes Probability Mode Decay Energy Daughter 100% α 9.2477MeV 217Ac Show Ultimate Decay Products Atomic Weight 221.021877983 Abundance None Mass Excess 20.379211MeV Binding Energy 7.656961MeV Magnetic Moment N/A Quadrupole Moment N/A   Show Isotope Symbols. Show only decay products of this isotope.

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