Question

1. Use the Shell Model to predict the most likely decay experienced by Nitrogen-17, and then find the daughter isotope for that decay. Here are the atomic numbers for a short segment of the periodic table in that region: Beryllium (4), Boron (5), Carbon (6), Nitrogen (7), Oxygen (8), Fluorine (9).

Answer 1

Total no of protons in the nucleus of Nitrogen is 7, so the number of neutron in the nucleus will be (mass number - 7). There are two stable isotope of Nitrogen, N14 and N15(this is very rare), all other isotopes of nitrogen are unstable. So the nucleus of N14 contains 7 neutrons and N15 contains 8 neutrons. Now the N17 isotope of Nitrogen has a mass number 17, so it has 10 neutrons in its nucleus, hence the neutron proton ratio in the nucleus of N17 is higher than than that of stable isotopes. So most likely decay of N17 will be a beta decay in which a neutron in the nucleus is converted into a proton, and an electron and anti neutrino is released. so the daughter neucleus after beta decay will have one more proton than N17, that is 8, and the mass number will be same, that is 17. so the daughter nucleus is oxygen(17) isotope.