is deltam 019 amu and the atomic mass of U235 is 2350 gmol

is (delta)m = 0.19 amu and the atomic mass of U-235 is 235.0 g/mol. Given that the heat of combustion of carbon is 393.5 kJ/mol, calculate the mass (in kg) of coal (i.e. carbon) that would have to burned to produce the same amount of energy produced when 0.10 g of U-235 undergoes this fission reaction.

Solution

0.1 gm U235 = 0.1/235 = 0.0004255 moles = 0.0004255 x6.023 x10^ 23 = 0.002563 x10^ 23 atoms,

delta m = (0.19x0.002563 x10^ 23) = 0.487 x10^ 20 amu ,

E = 931.5 x0.487 x10^ 20 MeV = 931.5x10^6 x 0.487x10^ 20 x1.6x10^ -19 =725.8 x10^ 7Joules

= 7.258 x10^ 6 KJ

moles of carbon for this combustion = ( 7.258 x10^ 6)/(393.5) = 18445.35

mass of Carbon = (12x18445.35) = 221344.3 gm = 221.344 kg