In: Chemistry
Carbon-14 decays as follows:
14 0 14
C ----> e + N
6 -1 7
isotopic masses are 14.00307 for nitrogen-14 and 14.00324 for carbon-14. What energy change (kJ/moles) occurs in the beta decay of C-14? NOTE: Do I use these two masses to get the mass defect or do I use the mass of protons and nuetrons to find the mass defect of each one and then subtract the two?
mass defect = mass of product - mass of reactant
= (14.00307 + 0.000548579 ) - 14.00324
= 0.0003785799 amu
1 amu =1.66053892 × 10-27 kilograms
mass defect in Kg = = 0.0003785799 x 1.66053892 × 10-27 = 6.286 x 10-31 kilograms
binding energy = mass defect x C^2
= 6.286 x 10-31 x (3 x10^8)^2
= 5.6576 x 10^-14 J
= 5.6576 x 10^-17 kJ ( divide by avagadro number = 6.023 x10^23 )
= 3.40 x 10^10 kJ /mol