Do Now : K1+ (cation) ionization energy atomic size What ion will be formed when a K atom loses 1 e-? K1+ (cation) Match the following important vocab words w/the correct definition: ionization energy atomic size Volume or radius of an atom Energy required to remove an e- from an atom in the gas phase K + energy K1+ + e- IONIZATION ENERGY

Electronegativity A super duper important idea for chemists… It is the measure of the ability of an atom’s nucleus to attract electrons from a different atom within a covalent bond. (Higher electronegativity means a stronger pull on e-)

Summary of Periodic Trends Atomic radius decreases Ionization energy increases Electronegativity increases Ionization energy decreases Electronegativity decreases Atomic radius increases 1A 2A 3A 4A 5A 6A 7A Ionic size (cations) Ionic size (anions)‏ decreases decreases

Periodic Table Groups