1. Shielding Effect Valence + - - nucleus - Electrons - Electron Shield “kernel” electrons Kernel electrons block the attractive force of the nucleus from the valence electrons

2. http://www.bcpl.net/~kdrews/properties/properties.html#Atomic ATOMIC RADIUS

3. Periodic Trends in Atomic Radii LeMay Jr, Beall, Robblee, Brower, Chemistry Connections to Our Changing World , 1996, page 175

4. ELECTRONEGATIVITY—a measure of how strongly an atom’s nucleus pulls electron density toward itself when in a bond. *assigned (Pauling scale) *only useful in comparing two atoms (MEANS THAT ALL YOU CARE ABOUT IS THE DIFFERENCE!!!!)

5. Which has greater electronegativity in each compound?

7. the more tightly an electron is held, the more energy is required