Question

If a vial of I-131 contains 100 mCi on Dec 1, approximately how much activity will it contain on Dec 17 provided none is withdrawn?

a. 6.25 mCi
b. 12.5 mCi
c. 25 mCi
d. 50 mCi

Answer 1

The vial of I-131 will contain approximately 12.5 mCi on Dec 17.

Step-by-step explanation:

To calculate the activity of the vial on Dec 17, we need to consider the half-life of I-131. The half-life of I-131 is 8.04 days.

Using the formula A = A_0 * (1/2)^(t/T), where A is the final activity, A_0 is the initial activity, t is the time in days, and T is the half-life, we can calculate the final activity.

In this case, the initial activity is 100 mCi and the time is 16 days (Dec 17 - Dec 1). Plugging in these values, we get A = 100 * (1/2)^(16/8.04) ≈ 12.5 mCi.