91Ó°ÊÓ

(Chemical Connections \(9 \mathrm{B}\) ) How does radon- 222 produce polonium-218?

(Chemical Connections 9C) Why is high-energy radiation exposure of water in the body dangerous to rapidly dividing cells?

Phosphorus- \(32\left(t_{1 / 2}=14.3 \mathrm{h}\right)\) is used in the medical imaging and diagnosis of eye tumors. Suppose a patient is given \(0.010 \mathrm{mg}\) of this isotope. Prepare a graph showing the mass in milligrams remaining in the patient's body after one week. (Assume that none is excreted from the body.

During the bombardment of argon- 40 with protons, one neutron is emitted for each proton absorbed. What new element is formed?

Neon-19 and sodium-20 are positron emitters. What products result in each case?

The half-life of nitrogen- 16 is 7 seconds. How long does it take for \(100 \mathrm{mg}\) of nitrogen- 16 to be reduced to \(6.25 \mathrm{mg} ?\)

Do the curie and the becquerel measure the same or different properties of radiation?

Selenium-75 has a half-life of 120.4 days, so it would take 602 days (five half-lives) to diminish to \(3 \%\) of the original quantity. Yet this isotope is used for pancreatic scans without any fear that the radioactivity will cause undue harm to the patient. Suggest a possible explanation.

Which radiation will cause more ionization, X-rays or gamma rays?

Americium-241, which is used in some smoke detectors, has a half-life of 432 years and is an alpha emitter. What is the decay product of americium- 241 , and approximately what percentage of the original americium-241 will be still around after 1000 years?