Anatomy Chemistry

Chemistry Notes in Physiology Chemistry notes in Physiology: Atoms Atom?the basic unit of an element An atom consists of subatomic particles: Proton This has a ( + ) charge The number of protons in an atom is called atomic number Neutron This has no charge Electron This has a ( ? ) charge The number of electrons is usually equal to the number of protons ? Both the proton and the neutron are in the nucleus The sum of the proton and neutron is called atomic mass Shell = energy level 1st shell has 2 electrons 2nd shell has 8 electrons Valence electrons are the outermost electrons ? Isotopes = same atomic number, but different atomic mass Isotopes will differ in the number of neutrons For example: Hydrogen has 1 proton Deuterium has 1 proton and 1 neutron