You can put this solution on YOUR website! The half-life of radium is 1690 years.
If 80 grams are present now, how much will be present in 420 years?
:
The radioactive decay formula
A = Ao*2^(-t/h), where
A = amt remaining after t time
Ao - initial amt
t = time of decay
h = half-life of substance
:
A = 80*2(-420/1690)
use calc
A = 80 * .84176
A = 67.32 grams after 420 yrs
