chpt 4 vocab

smallest particle of an element that retains its identity in a chemical reaction

weighted average of the masses of the isotopes of an element

unit of mass equal to one-twelfth the mass of a carbon-12 atom

number of protons in the nucleus of an atom of an element

stream of electrons produced at the negative electrode of a tube containing a gas at low pressure

first theory to relate chemical changes to events at the atomic level

negatively charged subatomic particle

veritcal column of elements in a periodic table

atoms of the same element that have the same atomic # but different atomic masses due to a different # of neautrons

total # of protons with no charge and a mass of 1 amu

subatomic particle with no charge and a mass of 1 amu

tiny, dense central portion of an atom, composed of protons and neutrons

horizontal row of elements in the peroidic table

arrangement of elements in which the elements are seperated into groups based on a set of repeating properties

positively charged subatomic particle found in the neucleus of an atom