Orbital
mathematically defined area where electrons have the highest probability of existing
Valence Electrons
electrons in outermost shell
Core Electrons
not valence electrons, do not participate in chemical bonding
Representative Elements
reactive elements; inner shells are completely filled, outer shell is incomplete (s or p subshells are incomplete)
Transition Elements
the metals occupying the middle of the periodic table (d and f blocks)
Lanthanide Series
4f elements
Actinide Series
5f elements
Ionization Energy
the energy required to remove an electron from a gaseous atom or ion
First Ionization Energy
energy required to remove the first valence electron
Second Ionization Energy
energy required to remove the second valence electron
Electron Affinity
how easy it is to gain an electron (negative = easy, positive = difficult)
Atomic Radius
distance from nucleus to the outermost electron orbital
Quantum Number
4 numbers that describe the state of an electron
Ground State
lowest energy state of an electron
Excited State
when an electron temporarily exists in an energy state greater than its ground state
Electromagnetic Radiation
electric and magnetic disturbances, no mass or charge, travels in form of photons
Wavelength
distance between two adjacent crests/ troughs
Frequency
the number of times something occurs in a set period of time
Hertz
unit for 1 per second (sec^-1)