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ssss1 Three types of radioactive decay: alpha decay, beta decay, and electron capture (gamma decay) and the changes in nuclear configuration that occur as the parent isotope decays into a daughter isotope.
ssss1 The 14‐step radioactive decay sequence that occurs in the conversion of the radioactive isotope238U into the stable isotope206Pb.
Parent isotope Daughter isotope Decay process Half‐life Uranium‐238 Thorium‐234 Alpha 4.5 × 109 years Thorium‐234 Protactinium‐234 Beta 24.5 days Protactinium‐234 Uranium‐234 Beta 1.1 minutes Uranium‐234 Thorium‐230 Alpha 2.3 × 105 years Thorium‐230 Radium‐226 Alpha 8.3 × 104 years Radium‐226 Radon‐222 Alpha 1.6 × 103 years Radon‐222 Polonium‐218 Alpha 3.8 days Polonium‐218 Lead‐214 Alpha 3.1 minutes Lead‐214 Bismuth‐214 Beta 26.8 minutes Bismuth‐214 Polonium‐214 Beta 19.7 minutes Polonium‐214 Lead‐210 Alpha 1.5 × 10−4 seconds Lead‐210 Bismuth‐210 Beta 22.0 years Bismuth‐210 Polonium‐210 Beta 5.0 days Polonium‐210 Lead‐206 Alpha 140 days