Final answer:
Cobalt-60 undergoes beta decay which can be represented by the equation ^60_27Co \rightarrow ^60_28Ni + \beta^- + \gamma. It has a half-life of 5.27 years which means its activity is halved every 5.27 years and must be replaced regularly in medical treatments.
Step-by-step explanation:
Cobalt-60 is a synthetic radioisotope widely used in cancer treatment. It is produced through the neutron activation of Co-59, which results in Co-60. This isotope undergoes beta decay, emitting beta particles and gamma rays, which can be focused on small areas to treat cancer. The equation representing the decay of Co-60 is:
^60_27Co \rightarrow ^60_28Ni + \beta^- + \gamma
Here, Co-60 decays into Ni-60, and during this process, a beta particle (\beta^-) and gamma radiation (\gamma) are emitted. Cobalt-60 has a half-life of approximately 5.27 years, which means its activity, and thus its intensity of radiation, is halved every 5.27 years. This decay process follows first-order kinetics. Because of its radioactive nature, it must be replaced regularly in medical applications to maintain its effectiveness in cancer therapy.