Whole number rule called the neutron. The fact that the atomic nucleus is composed of protons and neutrons was rapidly accepted and Chadwick was awarded the Nobel Prize in Physics in 1935 for his discovery. The modern form of the whole number rule is that the atomic mass of a given elemental isotope is approximately the mass number (number of protons plus neutrons) times an atomic mass unit (approximate mass of a proton, neutron, or hydrogen-1 atom). This rule predicts the atomic mass of nuclides and isotopes with an error of at most 1%. Whole number rule The whole number rule states that
Charge number having stripped off all electrons, the charge number is identical with the atomic number "Z", which corresponds to the number of protons in ordinary atomic nuclei. Unlike in chemistry, subatomic particles with electric charges of two elementary charges (e.g. some delta baryons) are indicated with a superscript "++" or "−−". In chemistry, the same charge numbers are usually indicated as superscript "+2" or "−2". In particle physics, the charge number is a (derived) flavor quantum number. For color-charged particles like quarks and hypothetical leptoquarks, the charge number is a multiple of 1/3. Charge number Charge number ("z") refers to a