•+Periodic+Trends

=Ionization Energy is the Energy that it takes to remove an electron= =from a gaseous atom or ion to produce a gaseous cation. (+) Yes, strange as it may seem, I said gaseous.=

=Electron Affinity is the Energy Released when an electron is added to a gaseous atom to form an anion (-)=



=Actual Electron Affinity Values. Note that most values are negative (exothermic - favorable). Only the Noble Gases and Alkali earth Metals are positive (endothermic - unfavorable).=



= Shift to lower energies of ionization from B to N is due to shielding of electrons in p orbitals by electrons in s orbitals. Therefore the first three p electrons are easier to remove than expected. The shift to lower ionization energies from O to Ne are due to the fact that these contain paired p electrons, making them easier to remove. =