Question #369c9
1 Answer
Nov 3, 2014
The half-life would be 213,000 years for this isotope.
To get this answer, look at the change between your starting and ending amounts. You began with 800 g and this was halved 3 times (800 g - 400 g - 200 g - 100 g). Divide the total time of 639,000 years by the number of half-lives (3) to get the answer of 213,000 years for each half-life. When the number of half-lives is a whole number, this method works well.
Hope this helps.
