Physics (Radiation) Questions
 

Lets start with this.

140-Ba decays to 140-La with a half-life of 12.8 days and the 140-La decays to stable 140-Ce with a half-life of 40.5 hours. A radiochemist, after precipitating 140-Ba, wishes to wait until she has a maximum amount of 140-La before separating the 140-La from the 140Ba. How long should she wait? How much 140-La will she collect?

Consider it like a kinetic process

140Ba ---(k1)---> 140 La ---(k2)---> 140Ce

You should be able to write two ODE's for Ba and La based on the half lives. Solve for the two. At first glance, it looks like it will involve a 1st order linear ODE.

could you clarify further please? thank you

hobo,

Check out. You want to maximize the concentration of your intermediate, using the old calculus.