Nuclear decay chain,actinium series. Diagram of the nuclear decay chain of uranium-235 (U-235) with isotopes (shown by chemical symbols) plotted by mass number (A) against atomic number (Z). Isotopes are colour-coded by their primary decay route (purple,red arrows: alpha decay; blue,blue arrows: beta decay). Decays are rare (dotted lines) or dominant (solid lines). The dominant route (yellow) ends with the stable (green) lead-207 (Pb-207). Other elements in this natural decay chain are: protactinium (Pa),thorium (Th),actinium (Ac),radium (Ra),francium (Fr),radon (Rn),astatine (At),polonium (Po),bismuth (Bi),and thallium (Tl) |