Atoms and Periodic Table

Atom

Smallest particle of an element

Periodic Table

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

subatomic particles

electrons, protons, neutrons

Isotopes

Atoms with the same number of protons but different numbers of neutrons

Atomic number

the number of protons in the nucleus of an atom

Symbol

Mass Number

the total number of protons and neutrons in the nucleus of an atom

Atomic Mass

the weighted average of the masses of the isotopes of an element

Bohr Model

model of an atom that shows electrons in circular orbits around the nucleus

Lewis Dot Diagram

a model that uses electron-dot structures to show how electrons are arranged in molecules

Ions

positively and negatively charged atoms

Groups

Vertical columns on the periodic table

Periods

Horizontal rows on the periodic table

Families

Another word for groups, columns of elements on the periodic table

valence electrons

Electrons on the outermost energy level of an atom