Physics
posted by Mariana .
How much energy is released in the beta decay of 14 C?
Since carbon14 decays into Nitrogen14,
the mass of carbon 14 is 14.003242 and the mass of nitrogen 14 is 14.003074, What I did was:
(14.00324214.003074)u * 931.5 MeV/c^2 = (0.156 MeV/c^2)*c^2 = .156 MeV
but that's not the answer, am I doint something wrong?

Did you include the rest energy of the electron emitted in the beta decay process?
You can neglect the neutrino rest mass energy, since its mass is nearly zero. It does carry significant momentum. 
You are right, considering the mass of the electron emitted I got .352 MeV, which is the correct answer. Everywhere I looked on the internet said to neglect this mass, but I guess it does make a difference. My answer was negative though, does that mean that I only consider the absolute value of whatever I get?