Question

During the testing process for some pharmaceuticals, the drug is \"tagged\" with a radioactive material. This way researchers can determine if the pharmaceutical is going to other parts of the body than the intended target and what effect it has on the non-target areas. By adding this radioactive tag to the pharmaceutical, researchers can pinpoint all parts of the body and the concentration that accumulates in non-target areas.

One possible such tag is technetium-99, ⁹⁹Tc, which has a half-life of 6.05 hours.

1) How many ⁹⁹Tc nuclei are required to give an activity of 1.7 μCi?

N =

2) What is the decay constant for this isotope?

λ=

3) Suppose the drug containing the amount of ⁹⁹Tc calculated in part (a), were injected into the patient 1.2 hours after it was prepared, what would its activity be at that time?

R =

Answer 1

Sol N = 1.7 uci = 1.7 * 3.7 X104 N = 6.298104 B9 N = No e ett = Now, a=decay constant = ln 2 T112 0,6931 = = 3.182x10-5 51 6.05X3600 Ans 2 - N= No e da No 9x104 3.182x10-5 6.2.9 X10 1.976x109 cetome Anst. => REZRADO -1.2 A = No 2-trinn 1.7 2 6.05 :.N=1.48 uci Ans 3.

In the answer of sub question please replace R with N. Its R = 1.48 microCi