Hey all, I've ran into a bit of a mess with this problem:
Cobalt-60, which undergoes beta decay, has a half-life of 5.26 yr.
(a) How many beta particles are emitted in 43.3 s by a 2.98-mg sample of 60Co?
(b) What is the activity of the sample in Bq?
Alright, here is what I've done so far to try to get a solution.
First off, I figured since you are given the half-life, you can easily find k and this got me 0.132 yr^-1.
After this I became confused as to what you do with the k value. I know once the correct Nt is found, it is multiplied by 1/60 and then Avagadro's number in order to get the particle number, but I don't know how to get the correct Nt value.
Further on, I know once you get the answer to part A, that number is multiplied by 4.186e-9 (the found k in seconds instead of years) in order to get the answer in Bq.
Help please :)