For each of the following, indicate if the number of half-lives elapsed is: 1. one half-life 2. two half-lives 3. three half-lives a. a sample of ce-141 with a half-life of 32.5 days after 32.5 days b. a sample of f-18 with a half-life of 110 min after 330 min c. a sample of au-198 with a half-life of 2.7 days after 5.4 days

Explanation:

The number of half-lives elapsed, n, is calculated dividing the time by the half-life time:

a. A sample of Ce-141 with a half-life of 32.5 days after 32.5 days

b. A sample of F-18 with a half-life of 110 min after 330 min

c. A sample of Au-198 with a half-life of 2.7 days after 5.4 days

periodic trends is an atom that gets larger as the number of electronic shells increase, the radius of atoms increases as you go down a certain group in the periodic table of elements. in general, the size of an atom will decrease as you move from left to right of a certain period.