1. The problem statement, all variables and given/known data Earlier in the book it was remarked that early in the history of nuclear physics the electrically neutral mass of nuclei now attributed to neutrons was considered to arise from neutral particles composed of combinations of protons and electrons (as opposed to neutrons in their own right as fundamental particles). Here we have a look at the spin statistics of the situation. Consider a nitrogen-14 (147N) nucleus. If the "protons + electrons" model were correct , would you predict N-14 to be spin-1/2 or spin-1 system? What about in the case of the "protons + neutrons" model? Spectroscopic evidence indicates that N-14 is a spin-1 system. Which model does this support? 2. Relevant equations Protons and electrons are both spin-1/2. Neutrons if they're fundamental particles are also spin 1/2. 3. The attempt at a solution I said, If a neutron were composed of protons and neutrons, then the number of protons in the neutrons would have to equal the number of electrons in order to have a neutral charge. So the neutron would have spin-1. Therefore sicne there are 7 protons, 7 neutrons and 7 electrons in our atom, the "protons + electrons" model predicts spin-1 system. If a neutron was just fundamental with spin-1/2 then the "protons + neutrons" model predicts spin-1/2 system. Spectroscopic evidence supports the "protons + electrons" model. I think I have a decent understanding on what the two models are trying to say. I guess the "protons + neutrons" model is just the idea that we know today that the nucleus is made up of protons and neutrons with electrons orbiting. And I guess the "protons + electrons" model is the idea that the neutrons are made up of protons and electrons, and that the nucelus still has protons and neutrons, in addition to electrons orbiting. But shouldn't the N-14 atom have Spin-1/2 and shouldn't the "protons + neutrons" model be correct?