ABSTRACT
The nucleus is made up of protons and neutrons. Protons have a positive electrical charge, while neutrons, as the name implies, are neutral. As we noted at the end of the last chapter, the proton and neutron masses are almost identical, being approximately 2,000 times the mass of the electron but differing by only about 0.1%. A typical nuclear size is about 10−14 m, about 1/10,000 (10−4) the size of the atom.
