Aufbau principle- an electron occupies the lowest-energy orbital that can receive it Continuous spectrum- a spectrum in which all wavelengths within a given range are included Diamagnetism- the property of a substance whereby it is wakly repelled by a magnetic field Electromagnetic Radiation- a form of energy that exhibits wavelike behavior as it travels through space Electromagnetic spectrum- consists of all electromagnetic radiation, arranged according to increasing wavelength Excited state- a state in which it has a higher potential energy than it has in its ground state Frequency- (nu) defined as the number of waves that pass a given point in a specific amount of time, usually one second Ground state- state of lowest energy of an atom Highest occupied energy level- the electron-containing main energy level with the highest principal quantum number Hund’s rule- orbitals of equal energy are each occupied by one electron before any one orbital is occupied by a second electron, and all electrons in singly occupied orbitals must have the same spin Inner-shell electrons- electrons not in the highest occupied energy level Line emission spectrum- produced when an electron drops from a higher-energy orbit to a lower energy orbit to a lower energy orbit Magnetic quantum number- indicates the orientation of an orbital about the nucleus Noble gas configuration-an outer main energy level fully occupied, in most cases, by eight electrons Noble gases- the group 18 elements Orbital- a three-dimensional region about the nucleus in which a particular electron can be located Orbital quantum number- indicates the shape of an orbital Pauli exclusion principle- no two electrons in the same atom can have the same set of four quantum numbers Photoelectric effect- the emission of electrons by certain metals when light shines on them Photon-An individual quantum of light Principal quantum number- symbolized by n, indicates the main energy levels surrounding a nucleus Quantum numbers- numbers that specify the properties of atomic orbitals and of their electrons Spin quantum number- has only two possible values -(=1/2, -1/2)- which indicate two possible states of an electron in an orbital Wavelength- (lambda) is the distance between corresponding points on adjacent waves