Atoms and the Periodic Table

the smallest part of an element that has all the properties of that element

two or more elements that are chemically combined to a certain ratio

two or more different substances mingled with each other but not chemically combined

Atoms of the same element but with different numbers of neutrons

the average mass for all known isotopes

Two or more atoms joined together; can be the same or different

arranges in order of size of atoms

the arrangement of electrons in an atom

group

period

alkali metals

alkaline earth metals

Halogens

noble gases