Half-Life Problems
15 Points (3 Points Each)
Name:__________________________ Date:____________ Period:______
Work all problems on a separate sheet of paper. Show all work as outlined on board.
Half-Life
Amount Remaining = Amount of Original Sample/2n
where "n" = the number of half lives that have elapsed
| Radionuclide | Half-Life |
| 24Na | 15 Hours |
| 131I | 8 Days |
| 60Co | 1925 Days |
| 14C | 5730 Years |
| 235U | 71,000,000 Years |
Which nuclide in the table above has the shortest half life?
What is the half life of 60Co in years?
If 24 days have passed, how many half-lives of 131I have elapsed?
If you start with 14g of 14C, how much will you have after 5730 years have elapsed?
How much 131I will remain after a year has passed, if you start with 1000 Kg?