Half-life And Decay

Half-life & C-14 Objective #1) TLW solve half-life problems 1) The half-life of polonium-210 is 138.4 days. How many milligrams of polonium-210 remain after 415.2 days if you start with 2.0 mg of the isotope?

2) Assuming a half life of 1599 years, how many years will be needed for the decay of 15/16ths of a given amount of radium-226?

3) The half life of radon-222 is 3.824 days. After what time will one-fourth of a given amount of radon remain?

4) The half-life of cobalt-60 is 5.27 years. How many milligrams of cobalt-60 remain after 52.7 years if you start with 10.0 grams?

Objective #2) TLW determine the age of a sample given its initial and final carbon14 content 1) You are scientist working for an archeologist. While looking for mummies in Egypt your archeologist comes across the bones of what he thinks is an Egyptian slave. You run a C-14 test on the bones and find 25 nanograms of C-14 in a sample of bone that would contain 800 nanograms of C-14 if the person had died yesterday. How old are our person’s bones assuming that the half life of C-14 is about 5730 years?

Bonus: Why is our archeologist’s assumption probably wrong?