Question

echnetium in the Body. As mentioned in a previous problem, Tc-99m is a common radioisotope used in medical imaging. It is a metastable isotope that emits low energy gamma radiation (140 keV) with a half-life of roughly 6 hours. This half-life is extremely long for a metastable state, which makes it useful for studying gamma emission. This particular radioisotope has a biological half-life of roughly 1 day while in a human, and an atomic mass of 1.627 ×× 10−25−25 kg/atom.

1. What is the effective half-life of Tc-99m while in a patient? h
2. If a patient is injected with 0.88 nanograms of Tc-99m, what is the initial activity of the Tc-99m immediately after being injected into the patient? Bq
3. What will be the activity due to the Tc-99m left in the patient’s body after 8.4 hours? Bq

Answer 1