Energy Level Diagrams

1. Hund’s rule – e- half-fill each orbital in a sublevel before pairing up Energy Level Diagrams 6s Pictorial representation of electron distribution in orbitals 5p 4d Aufbau principle – e- occupy the lowest energy orbital available p. 188 in text 5s 4p Pauli exclusion principle – max 2 e- per orbital (spin up and spin down) 3d E 4s 3p 3s 2p 2s n = 1 l = 0 ml = 0 ms = -½ 1s

2. Orbitals Being Filled 1 8 Groups 2 1s 1 3 4 5 6 7 1s 2s 2 2p 3s 3p 3 4p 3d Periods 4s 4 4d 5p 5s 5 La 5d 6p 6 6s Ac 6d 7 7s 4f Lanthanide series 5f Actinide series Zumdahl, Zumdahl, DeCoste, World of Chemistry2002, page 345

3. Energy Level Diagrams 6s 5p 4d 5s 4p 3d E 4s 3p 3s 2p 2s Anions - Add e- to lowest energy sublevel available. 1s

4. Energy Level Diagrams 6s 5p 4d 5s 4p Cations - Remove e- from sublevel with highest value of n. 3d E 4s 3p 3s 2p 2s 1s

5. Energy Level Diagrams 6s 5p 4d 5s 4p Cations - Remove e- from sublevel with highest value of n. 3d E 4s 3p 3s 2p 2s 1s

6. Energy Level Diagram of a Many-Electron Atom 6s 6p 5d 4f 5s 5p 4d 4s 4p 3d Arbitrary Energy Scale 3s 3p 2s 2p 1s NUCLEUS O’Connor, Davis, MacNab, McClellan, CHEMISTRY Experiments and Principles1982, page 177

7. 28 Ni 58.6934 Excited State 1s 2s 2p 3p 4s 3d 3s Pauli Exclusion 1s 2s 2p 3p 4s 3d 3s Hund’s Rule 1s 2s 2p 3p 4s 3d 3s Orbital Diagrams for Nickel 2 2 6 2 6 2 8 1s 2s 2p 3p 4s 3d 3s 2 2 6 2 6 1 9

8. Homework • p. 191 #3alt,4 • p. 197 #5

10. Electron Configuration • H 1s1 • Ca 1s22s22p63s23p64s2 • Pb 1s22s22p63s23p64s23d104p65s24d105p66s24f145d106p2 • Cl- 1s22s22p63s23p6 • Fe2+ 1s22s22p63s23p63d6 • Fe3+ 1s22s22p63s23p63d5 • Ca [Ar]4s2 • Cl- [Ar] • Fe2+ [Ar]3d6 Shorthand: [noble gas]

11. Cr 3d4 Cu 3d9 Electron Filling in Periodic Table s s p 1 2 d 3 K 4s1 Ca 4s2 Sc 3d1 Ti 3d2 V 3d3 Cr 3d5 Mn 3d5 Fe 3d6 Co 3d7 Ni 3d8 Cu 3d10 Zn 3d10 Ga 4p1 Ge 4p2 As 4p3 Se 4p4 Br 4p5 Kr 4p6 4 Cr 4s13d5 Cu 4s13d10 4f 4d n = 4 4p 3d Cr 4s13d5 4s n = 3 3p Energy 3s 4s 3d 2p n = 2 2s Cu 4s13d10 n = 1 1s 4s 3d

12. Homework • p. 194 #6-11 • p. 197 #1,2,6-10,13

13. Anomalous e- Configurations

14. Ferromagnetic – Fe, Co and Ni are smaller, closely packed atoms able to orient themselves in a magnetic field (group of these atoms oriented in the same direction – domain theory) , explains full magnetism

15. Paramagnetism – substances exhibit a weak magnetic attraction  believed to be caused by the presence of unpaired electrons Q: Which substances containing calcium, zinc, copper (II) and manganese(II) ions are paramagnetic? CaSO4(s) ZnSO4(s) CuSO4(s) MnSO4(s)

16. Quantum Challenge The arrangement of elements in the periodic table is a direct consequence of the allowed values for the four quantum numbers. If the laws of physics allowed these numbers to have different values, the appearance of the periodic table would change. Suppose, in a different universe, the quantum number ml has the allowed values of ml = 0,1,…+l. All other allowed values are unchanged so the set of allowed values is: n = 1,2,3… l = 0,1,2…n-1 ml = 0,1…+l ms = ½,-½

17. Task: • Design the periodic table for the first 30 elements. • Label the s,p and d block elements. • Shade or colour the noble gas-like elements. Show your work!!