# Homework Help: Thermal Neutron Capture from 55Mn to 56Mn

1. Feb 22, 2012

### Kromboy85

1. The problem statement, all variables and given/known data
In a reactor, we're making 56Mn by inducing thermal neutron capture.
2g sample of 55Mn is put into the reactor which has a flux of thermal neutrons of 3E13 neutrons/cm^2*s

Sample is in the reactor for 8 hours and then removed.

a. Calculate the amount and activity of the 56Mn at the moment of its removal.
b. Calculate the activity of the sample after its two hour trip from the reactors to the hospital.

2. Relevant equations
This is the part I'm having trouble with

I've got the number of molecules of 55Mn we start with.
N(55Mn) = 2.192*10^22 molecules

I am given the thermal neutron flux, but I'm not sure how to use that piece of information to get the production rate of 56Mn.

As for part b, I think I'll be able to get that once I get the N0, I should be able to use half life of 56Mn to get the numbers, but I'm stuck on part A and can't progress further.

3. The attempt at a solution