thorium series

noun Chemistry.

the radioactive series that starts with thorium and ends with a stable isotope of lead of mass number 208.

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British Dictionary definitions for thorium series

thorium series

noun

a radioactive series that starts with thorium-232 and ends with lead-208

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012