Chemistry Final Review: 1. Question: Know what is the atomic number, atomic mass, protons, neutrons & electrons Atomic number – is the number of protons in the nucleus of an atom of any element Atomic mass – is expressed in amu; is the wighted average Protons – are positively charged particles in the nucleus Neutron – are neutral, have no electrical charge Electrons – are negatively charged particles in the nucleus Atomic number = number of protons Atomic number – (minus) a...