Q Value for spontaneous fission and neutron induced fission

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bmarson123
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Homework Statement


What is the Q value in units of MeV in each of the following processes?

i) The spontaneous fission of 232U92 to 145La57 and 87Br35

ii) The neutron induced fission of 232U92 to 146La57 and 87Br35

Explain why heavy nuclei such as 232U92 do not usually undergo fission.

[Masses given in atomic mass units are 232U92 232.0372; 145La57 144.9217; 146La57 145.9255; 87Br35 86.9203; n 1.0087]

Attempt

There are loads of equations for different Q values depending on the type of decay it undergoes. I'm not sure which to use.

Also, I think I need to convert the atomic mass units into something else but I'm not entirely sure what?

I basically don't know where to start with it!
 
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bmarson123 said:
There are loads of equations for different Q values depending on the type of decay it undergoes. I'm not sure which to use.
Use what is given to you. You call these decays, but are they really that? What is a better name for the process in which a uranium nuclide becomes a lanthanum and a bromine nuclide?
bmarson123 said:
Also, I think I need to convert the atomic mass units into something else but I'm not entirely sure what?
Why convert? Use what is given to you.
bmarson123 said:
I basically don't know where to start with it!
Start by writing an equation for a given process, then make sure it conserves energy.