Neutron activation analysis was performed on small pieces of hair that had been taken from the exiled Napoleon after he died on the island of St. Helena in 1821. This procedure involves exposing the samples to a source of neutrons. Some (stable) arsenic nuclei, if present in the sample, will absorb a neutron. In Napoleon’s case the samples did contain abnormally high levels of arsenic, which supported the theory that his death was not due to natural causes.
(a) These results came from studying beta emissions of the resulting 76As, nucleus. Write the nuclear equation for the neutron absorption and use it to determine the arsenic isotope initially present in the hair.
(b) Write the nuclear equation for the sub-sequent beta decay of 76As. Use it to determine the nucleus after this decay.