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Homework Statement
(a) Cobalt has only one stable isotope, 59Co. What form of radioactive decay would you expect the isotope 60Co to undergo? Give a reason for your answer.
(b) The radioactive nuclei 21084Po emit alpha particles of a single energy, the product nuclei being 20682Pb.
(b) (i) Using the data below, calculate the energy, in MeV, released in each disintegration.
(b) (ii) Explain why this energy does not all appear as kinetic energy, Eα, of the alpha particle.
(b) (iii) Calculate Eα, taking integer values of the nuclear masses.
Nucleus, mass (u): 21084Po, 209.936 730; 20682Pb, 205.929 421; α-particle, 4.001 504.
(1 atomic mass unit, u = 931 MeV.)
Answers: (b) (i) 5.40(4) MeV, (iii) 5.30(2) MeV.
2. The attempt at a solution
(a) No idea. It can't be α, β, since the difference in the nucleon number is 1: 60Co → 59Co.
(b) (i) (209.936 730 - 205.929 421 - 4.001 504) * 931 = 5.404455 MeV.
(b) (ii) No idea. KE like 1 / 2 m v2? Or E = m c2? Maybe because we don't have mass in kg in this situation?
(b) (iii) Also no idea. Integer values like 209 - 205 - 4? Without digits?
Any help please?