1. Relating Electron Configuration to the Periodic Table 1s 2s 3s 4s 5s 6s 7s 2p 3p 4p 5p 6p 7p 3d 4d 5d 6d 4f 5f Au Au (1s 2 79 e - 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 6 5s 2 4d 10 5p 6 6s 2 4f 14 5d 9 )

2. Predict the Electron Configurations of the Following: Example: P P (1s 2 2s 2 2p 6 3s 2 3p 3 ) Co Co (1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 7 ) Sr Sr (1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 6 5s 2 ) O Fr Fr ( [Rn] 7s 1 ) O ( [He] 2s 2 2p 4 ) Am Am ( [Rn] 7s 2 5f 7 ) Core notation – use noble gas to represent core electrons

3. Electron Configurations of Negative Ions For negative ions add electrons to the last unfilled shell. P P (1s 2 2s 2 2p 6 3s 2 3p 3 ) O-O-O-O- O - ( [He] 2s 2 2p 5 ) P 3- P 3- (1s 2 2s 2 2p 6 3s 2 3p 6 ) O O ( [He] 2s 2 2p 4 ) O 2- O 2- ( [He] 2s 2 2p 6 )

4. Electron Configurations of Positive Ions For positive ions there are 2 rules: 1.e - in the outermost shell (largest n-value) are removed first. 2.If there are e - in both the s- & p- orbitals in the outermost shell, remove the p-orbital e - first. K K (1s 2 2s 2 2p 6 3s 2 3p 6 4s 1 ) Sn 2+ Sn ( [Kr] 5s 2 4d 10 5p 2 ) V2+V2+V2+V2+ V (1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 3 ) Sn Sn 4+ V K+K+K+K+ K + (1s 2 2s 2 2p 6 3s 2 3p 6 ) V 2+ (1s 2 2s 2 2p 6 3s 2 3p 6 3d 3 ) Sn 2+ ( [Kr] 4d 10 ) 5s 2 Sn 4+ ( [Kr] 4d 10 )

5. What do the orbitals look like?

6. p - orbitals d - orbitals

7. f - orbitals

8. Valence Electrons Valence electrons are the electrons in the outermost s- & p-orbitals K Sn V K (1s 2 2s 2 2p 6 3s 2 3p 6 ) 4s 1 V (1s 2 2s 2 2p 6 3s 2 3p 6 3d 3 ) 4s 2 Sn ( [Kr] 4d 10 ) 5s 2 5p 2 1 valence e - 4 valence e - 2 valence e -

9. Periodic Trends Atomic Radius Decreases from left to right across a period (due to increased charge on the nucleus) Decreases from left to right across a period (due to increased charge on the nucleus) Increases from top to bottom in a group or family (due to shielding effects & larger orbitals) Increases from top to bottom in a group or family (due to shielding effects & larger orbitals)Electronegativity The attraction an atom has for a shared pair of electrons in a covalent bond Increases from left to right across a period Increases from left to right across a period Decreases from top to bottom in a group or family Decreases from top to bottom in a group or family

10. Ionization Energy The energy needed to remove an electron. Increases from left to right across a period Increases from left to right across a period Decreases from top to bottom in a group or family Decreases from top to bottom in a group or family