Mass of Nuclide Remaining After a Fraction of a Half-Life

[jzwiep]

Homework Statement

You want to do an experiment using 47Ca (half-life=4.53 days). You will need 3.25 μg of the nuclide. What mass of CaCO3 (100% enriched in 47Ca) must you order if it will take 50 hours to be delivered to you from the nuclear facility where it is prepared?

Homework Equations

The Attempt at a Solution

4.53 days x 24 hrs/day = 108.72 hrs

50/108.72 = 0.4599 half-lives

(1/2)^0.4599 = 0.727

3.25 μg / 0.727 = 4.47 μg

Am I doing something wrong? All the ways I've seen to do this type of problem lead me to the same answer, but it says it's incorrect.

 

[Moorebc]

Homework Statement

You want to do an experiment using 47Ca (half-life=4.53 days). You will need 3.25 μg of the nuclide. What mass of CaCO3 (100% enriched in 47Ca) must you order if it will take 50 hours to be delivered to you from the nuclear facility where it is prepared?

...


Am I doing something wrong? All the ways I've seen to do this type of problem lead me to the same answer, but it says it's incorrect.

I don't think so but you haven't finished, read the question carefully!