Fluorine-18, which has a half-life of 110 min, is used in PET scans.b. If 100. mg of fluorine-18 is shipped at 8:00 a.m., how many milligrams of the radioisotope are still active when the sample arrives at the radiology laboratory at 1:30p.m.?

What is wrong with the following decay curve? Explain.

For each of the following, indicate if the number of half-lives elapsed is:1. one half-life2. two half-lives3. three half-livesc. a sample of Au-198 with a half-life of 2.7 days after 5.4days

Strontium-85, used for bone scans, has a half-life of 65 days.b. How long will it take for the radiation level of strontium-85 to drop to one-eighth of its original level?

What does it mean when we say that strontium-90, a waste product of nuclear power plants, has a half-life of 28.8 years?

Use the following decay curve for iodine-131 to answer problems a to c: (5.4) b. Complete the number of days on the horizontal axis.

Harmful chemical spills can often be cleaned up by treatment with another chemical. For example, a spill of H₂SO₄ might be neutralized by addition of NaHCO₃. Why is it that the harmful radioactive wastes from nuclear power plants cannot be cleaned up as easily?

The half-life for the radioactive decay of Ce-141 is 32.5 days. If a sample has an activity of 4.0 µCi after 130 days have elapsed, what was the initial activity, in microcuries, of the sample? (5.3, 5.4)