The Updated Nuclear Model

It was determined that the proton and neutron made up the nucleus of an atom. The nucleus is positively charged highly dense region in the center of an atom. It contains nearly all of the mass of an atom but takes up a negligible amount of volume. The nucleus which should fly apart is held together by the Strong Nuclear Force. This force is what is released in a nuclear explosion. The majority of the volume of an atom is taken up by the region known as the electron cloud. Electron have a mass 1/1000 that of a proton or neutron and contribute nearly nothing to the mass of the atom. Most diagrams including the one to the right do not show the correct scale of the cloud to the nucleus. Watch the video below to get a better idea of the composition of an atom.