In reply to Axil Axil's message of Wed, 24 Apr 2013 19:51:00 -0400: Hi, [snip] >No mistake, but check me > > > >so..for 1 nickel 62... > >?mass = 28x1.00727647amu + 34x1.00866492amu - 61.928345amu = 0.5700034
You are adding the masses of naked protons and neutrons, but subtracting the mass of the entire atom, with the electrons included. If you do this correctly, you get a difference 0f 4.73 MeV. However you are comparing apples with oranges, because you start out with different ingredients for Ni than you do with Cu, i.e. different numbers of neutrons and protons. So you can't just subtract the binding energies and expect to get a useful number. A valid calculation of the change in energy can only be made by comparing the masses of the final products, i.e. Ni62 and Cu62. Note also that the binding energy release for Ni is greater than that for Cu, which means that the positive difference you got should have been a negative difference (you put the wrong one first in the subtraction), or alternatively you were attempting to calculate the energy of the Cu to Ni conversion, not the Ni to Cu conversion. > > > >so..for 1 copper 62... > >?mass = 29x1.00727647amu + 33x1.00866492amu - 61.932616amu = 0.5643440 > > > >Difference in binding energy = 0.00565941amu > > > >In MeV = 5.2703255625 Regards, Robin van Spaandonk http://rvanspaa.freehostia.com/project.html
