1. Academic Chemistry Class Notes April 9, 2015 Periodic Trends of the Elements

2. Atomic Radius - the size of an atom. Increases to the left and down on the periodic table.

4. Electron levels are added as you go down a group. (atomic size increases)

5. The nuclear charge increases as you go across a period toward the right. (atomic size decreases)

6. Ionic Radius The negative ion (anion) is always larger than the neutral atom.

8. The positive ion (cation) is always smaller than the neutral atom.

10. Electronegativity - the force of attraction an atom has for the electrons shared in a chemical bond

12. Ionization Energy - the energy required to remove the first electron from a neutral gaseous atom.

15. The radioactive elements in any group are generally found at the bottom of the periodic table.