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Fission and isotopes

1a.) You have 16 electrons, 16 protons, and 16 neutrons. You can combine them to make 8 Helium (He-4) atoms, 4 beryllium atoms (Be-8), 2 oxygen atoms (O-16), or one sulfur atom (S-32). What will you do to make the most stable product?
Info:
H-1 1.00782505 amu
He-4 4.0026033 amu
Be-8 8.0053052 amu
O-16 15.9949146 amu
S-32 31.972072 amu
(I want to say its sulfur because it weighs more but i'm not sure)
b.) calculate the energy released in the fission reaction
Be-8 ------ 2 He-4
( I got -1.28x10^(-6) MeV/Be) but i don't think i did it correctly)

2.) the molecule benzene has a molecular formula C6H6. If the relative abundance of Carbon-13 is 1% of that for carbon-12, what can be said about the ratio of the two parent ions corresponding to masses of 78 and 79 amu

Solution Preview

Atomic nuclei are stable subject to the condition that they contain an adequate number of neutrons, in order to "dilute" the concentration of positive charges brought about by the protons. Nuclear stability thus depends on the atomic number (Z) and on the mass number (A). This determines the mass defect, which in turns determines the binding energy. The greater the binding energy per nucleon in the atom, the greater the nuclear stability.

Mass defect can be calculated by using the equation below. Dm = [ Z(mp + me) + (A-Z)mn ] - matom Binding energy can be calculated by ...

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