Question

Use the following information to answer the next question Food irradiation is sometimes used as a means of preserving perishable foods. A 320 g mass of cobalt-60 is used as a source of gamma radiation in an irradiation device. The half-life of cobalt-60 is 5.3 years. As the radiation released by the cobalt-60 declines, the device becomes less efficient. The cobalt-60 also undergoes beta negative decay. 3. Complete the following: Determine the amount of cobalt-60 remaining in the device after 10.0 years. Write the beta negative decay equation for the decay described above. Explain, in terms of quark changes, what changes occur in the nucleus of the atom as it undergoes beta negative decay. Determine the wavelength of the gamma photon released in the decay above if the photon has an energy of 1.33 MeV. .

Answer 1

60 Now THE 5.3 years - THE - at uro corone, Charge of quark U=+2/3 3. No of atom in 320g of Co is 5.33 male. 0.693 0.13 year Now no. of atom left at time t= 10 year N(t) = Noe 0.13x10 5.334 e - 1.44 soll Now 1.44 male = 1.44X60 = 86.5 g. after 10 year 86.598 Co remain. t vel decay Proton telectron & antin utrino. in quard nature, ddu – Weed te- & (neuron) (Preton) 69 60 GO Co 27 Ni te Jo Beta minus neutron d=-1/3 if Pronton Energy is t = ho=h i hc 1.33 Mev a= ne 1-33 Mev 2= 6.626 x 18-34 x 3 x108 1- 33x10 6xl. 6x 10 19 = 9.34x10-13 m