Work required to disassemble a helium atom

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To disassemble a helium atom, the mass of its constituent particles is compared to the atom's rest mass, revealing a mass difference of 0.030377u. This mass difference can be converted to energy using the equation E=mc^2, with 1 u corresponding to 931.49 MeV. However, the calculation presented incorrectly applies the conversion, leading to confusion about unit consistency. The discussion highlights the need for clarity in using mass-energy equivalence and proper unit conversions. A hint is requested to correctly apply the conversion factor in the context of calculating the energy required for disassembly.
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Homework Statement



A helium atom has a rest mass of He = 4.002603u. When disassembled into its constituent particles (2 protons, 2 neutrons, 2 electrons), the well-separated individual particles have the following masses: p = 1.007276u, n= 1.008665u, e = 0.000549u.

How much work is required to completely disassemble a helium atom? (Note: 1 u of mass has a rest energy of 931.49 MeV.)

Homework Equations



E=mc^2

The Attempt at a Solution



2(1.007276u + 1.008665u + 0.000549u) = 4.03298u

4.03298u - 4.002603u = .030377u

E = (0.030377u)*(931.49 MeV/u)*(3.0*10^8)^2

E = 2.5466*10^18 MeV

*I tried using c = 2.9979*10^8, however it is still wrong.
 
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Did you notice that the units of (0.030377u)*(931.49 MeV/u)*(3.0*10^8)^2 are m4/s4?

The conversion 931.49 MeV/u is not a conversion between one mass and another mass, so multiplying by this and then using E=mc2 afterwards is pretty suspect
 
Office_Shredder said:
Did you notice that the units of (0.030377u)*(931.49 MeV/u)*(3.0*10^8)^2 are m4/s4?

The conversion 931.49 MeV/u is not a conversion between one mass and another mass, so multiplying by this and then using E=mc2 afterwards is pretty suspect

I had considered this. I'm honestly not sure where else to use the conversion. Can you give a hint? Am I correct to solve for the change in mass?
 

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