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The Structure of Matter

MATTER anything which occupies space and has inertia
ATOM the smallest particle of an element that has the characteristic properties of the element
MOLECULES the smallest subdivision of a substance having the characteristic properties of that substance
SUBSTANCE any material that has a definite, constant composition
COMPOUNDS are formed by the chemical union of two or more elements in definite proportions
NIELS BOHR proposed the most widely help theory of atomic structure
NUCLEUS contains most of the mass consisting of nucleons (protons and neutrons)
PROTONS elementary positive particles
NEUTRONS elementary neutral particles
ELECTRONS carry a single negative charge
ATOMIC NUMBER the # of protons or positive charges in the nucleus of an atom
MASS NUMBER the total # of protons and neutrons in the nucleus of an atom
ISOTOPES atoms that have the same # of protons but different # of neutrons
PERIOD TABLE table where elements are arranged from the lightest to the heaviest, or from the lowest atomic # to the highest
VALENCE determines the combining ability of the atom by the # of electrons in the outermost shell in the atom
IONIC BOND when 2 atoms are attracted to each other
COVALENT BOND the sharing of outer orbital electrons
IONIZATION the addition or removal of orbital electrons
ATOMIC # denoted by symbol Z
MASS # denoted by the letter A
NUCLIDE any particular kind of atom, having a specific number of protons and neutrons
Created by: ladyhope819