WARM UP Write configurations for the following elements, using noble gas notation: S Co Au Cs

Periodic Trends

Effective Nuclear Charge Amount of “hold” the nucleus exerts Increases left to right Decreases top to bottom

Atomic Radius Size of the atom Decreases left to right Increases top to bottom

Ionization Energy Energy it takes to remove an electron Increases left to right Decreases top to bottom

Electron Affinity / Electronegativity How good an atom is at pulling in an electron Increases left to right Decreases top to bottom (generally)

WRAP UP Which atom is larger? Which atom has a stronger nucleus? Ca or Fr Which atom has a stronger nucleus? Al or O Which atom has a higher electron affinity? Na or Cl Which atom has a higher ionization energy?

WARM UP List each of the 4 properties that exhibit periodic trends, and describe the trend of each of them.

WRAP UP Which atom is larger? Which atom has a stronger nucleus? Al or I Which atom has a stronger nucleus? B or In Which atom has a higher electron affinity? S or Ne Which atom has a higher ionization energy? Li or Ca