Chadwick's Neutron Discovery
Onion the Omniscientist: I’m getting there… you’re cluelessness is getting out of hand… Anyways, it was found through an experiment of Rutherford while he was experimenting with positive rays. Since a hydrogen atom is the simplest atom with just one proton and an electron, he ionized them to separate the nucleus from the electrons.
Onion the Omniscientist: Yes, there was more! He put some paraffin wax near the beryllium and some of the neutrons that resulted hit the wax, which released protons. (This proved that there were neutrons because at first they had mistaken the neutrons for some really strong type of gamma ray but Chadwick concluded it wasn’t possible for the photons of the gamma rays to contain so much energy.) So he inferred that it had to be neutrons because they have similar masses to protons and would have been able to push the protons out of the wax.
to learn about Milikan's Oil Drop Experiment!