Exam 9: The Nucleus, Radioactivity, and Nuclear Medicine

A 200.0-ng sample of sodium-24 was stored in a lead-lined cabinet for 45 hours.The half-life of sodium-24 is 15 hours.How much sodium-24 remains?

The isotope decays to by emitting radiation.What type of radiation is emitted?

What is the charge of a beta particle?

When a molecule is hit by gamma radiation, which of the following is likely to occur?

A 50-mg sample of iodine-131 was placed in a container 32.4 days ago.If its half-life is 8.1 days, how many milligrams of iodine-131 are now present?

Which radioactive emission can be stopped by a few sheets of paper?

Which one of the following radioactive isotopes is used to diagnose coronary disease?

In the general symbol for a nucleus, how is the number of neutrons calculated?

What is the correct nuclear symbol for the unknown product "X" in the nuclear equation shown below?

Which nuclear particle is identical to an He²⁺ ion?

How many half-lives are needed for a 400.0 ng sample of a radioactive isotope to decay to 12.5 ng?

Which type of radiation is negatively charged?

When the strength of a radioactive source is specified in curies, it provides no information on the biological effects of the radiation.

What statement concerning the half-life of a radioactive isotope is FALSE?

What nuclear process involves heavy nuclei splitting into lighter nuclei?

What is the name given to the energy that is responsible for holding the protons and neutrons together in the nucleus?

When a nuclear reaction is balanced, which of the following is TRUE?

The half-life of tritium ( ) is 12 years.How long does it take for 16.0 ng of tritium to decay to the point where 2.0 ng remains?

A metastable isotope decays by emitting a gamma ray.

What information is conveyed by the "m" in ^99mTc?