How Does E=mc2 Explain Energy Release in Nuclear Fission?

AI Thread Summary
E=mc² explains energy release in nuclear fission by illustrating the conversion of mass into energy during the reaction. In a typical fission reaction, such as the splitting of Uranium-235, a small amount of mass is lost, resulting in a significant energy release, calculated to be 171.74 MeV. This energy output is vastly greater than that from chemical reactions, which typically release energy in the range of a few electron volts. The discussion highlights the importance of understanding mass versus mass number and the differences between nuclear and chemical equations. The conversion of MeV to joules is straightforward using Avogadro's number and the electron volt to joules conversion factor.
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1. Homework Statement [/b]

The overall question is:
For this assignment explain how the E=mc2 equation applies to nuclear fission. In your answer illustrate your explanation with an example, being sure to distinguish between mass and mass number, and explain how a nuclear equation differs from a chemical equation. In addition compare the energy released during fission with energy produced from a typical chemical reaction (such as fossil fuel oxidation). It may be useful for you to consider that the combustion of methane releases 50.1 kJ/g - how much mass is lost to produce 50.1 kJ?

I put it all here so hopefully someone can make sense of my anwer below. I welcome any suggestions!

3. The Attempt at a Solution [/b]

Started by inventing a reaction: 92U235 + 0n1 -> 37Rb90 + 55Cs143 + 3 0n1. (typical of a nuclear fission reaction.) The actual atomic masses of these are:
Rb90 = 89.91481
Cs143 = 142.92732.
2 0n1 = 2.01732
Sum = 234.85945. Now subtract:
U235 = 235.04392 to get
loss = 0.18447. One AMU = 931 Mev, so 171.74 Mev liberated by the fission. Chemical reactions produce energies on the order of a few electron volts.

This is where I stop...do I need a table of energy conversion values to convert AMU per mole to joules per mole, and then do a bit of arithmetic? Thanks for helping me out!
 
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You already have the energy released (MeV) per U235 atom. The energy release per mole is that times Avogadro's number. Once you have the result in MeV, you don't need a table. 1 electron volt = 1.60217646 × 10^(-19) joules. I just pasted that out of Google.
 
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