Chemistry Chapter 5 Ionization Energy

Period Trends

As atomic number increases across a row/period/series, ionization energy will increase

Group Trends

As atomic number increases within a family/group/column, ionization energy will decrease

Ionization Energy (IE)

Energy required to remove an electron (from valence shell) from an atom

First ionization energy

Energy required to remove the most loosely held electrons (from valence shell) from an atom

Reason for period trends

Going from metals to nonmetals - closer to octet (stable), which will take more energy to remove electron(s)

Up

Ionization energy increases when going _____ of the periodic table (horizontally)

Right

Ionization energy increases when going to the _____ of the periodic table (vertically)

Reason for group trends

Larger atomic radius Shielding effect