If you started with 100 grams of Potassium-40 how much would reamin Potassium-40 after 3.9 x 10 to the 9th years?
Earth Science - drwls, Saturday, May 26, 2012 at 2:29am
The half life of K-40 is 1.3*10^9 years.
That is something they should have told you, or which you have to look up.
3.9*10^9 years (the approximate age of the earth) is three half lives.
100g*(1/2)^3 = ??
Earth Science - jeff, Thursday, January 7, 2016 at 4:26pm