Question

The half-life of 199Au is 3.14 days.

a.)Convert the half-life to units of seconds.

b.) What is the decay constant (in s⁻¹) for this isotope?

c.) Suppose a sample of ¹⁹⁹Au has an activity of 0.360 µCi. What is this activity expressed in the SI unit of becquerels (Bq)?

d.) Suppose a sample of ¹⁹⁹Au has an activity of 0.360 µCi. What is this activity expressed in the SI unit of becquerels (Bq)?

e.) Now suppose that a new sample of ¹⁹⁹Au has an activity of 7.00 mCi at a given time.

How many half-lives will the sample go through in next 40.2 days? (Enter your answer for the number of half-lives to at least one decimal place.)

f.) What is the activity of this sample (in mCi) at the end of 40.2 days?

Answer 1