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Calculate the energy released when isotope of carbon, 146c , decays by β− emission. the atomic mass of 146c is 14.003242 u , the atomic mass of 147n is 14.003074 u . assume that the neutrino has no mass.

1 Answer

7 votes
The correct answer is: 156.49 keV (0.15649MeV)

Step-by-step explanation:
Since

E = mc^2

Where E = Energy = ?
m = mass = (14.003242 - 14.003074) amu = 1.68*10^-4amu

Also 1amu * c^2 = 931.5 MeV

Plug in the values in the equation:
E = (1.68*10^-4)*(931.5 MeV) = 0.15649 MeV = 156.49 keV
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