Isoopes : LUSENET : Introductory Geology, Oswego State : One Thread

In the notes there is a chart explaining half-lives. After 1 half life the parent and the daughter has the same amount. I thought that when the parent radioisotope decays eventually stable daughter isotopes are formed. If it is decayed how can parent and daughter isotopes be the same? I don't understand.

-- Jihan Antrobus (, March 26, 2001


After one half life the parent and daughter will be the same but as time continues, the second half life will be 1/2 of what is left or 1/4 of the original and the daughter will be 3/4 of the original parent. take half of the parent at each half life and add that to the daughter. I got this from the example Dr Gabel wrote on the chalk board. eventually you will get a stable or daughter isotope. It may take many half lifes to get a stable isotope.

-- Sandra Feocco (, April 05, 2001.

Moderation questions? read the FAQ