1. Electron Configuration UNIT 4 – QUANTUM MODEL:

2. Warm Up Where are the s, p, d, f orbitals located on the periodic table?

3. Agenda Quiz Grade Homework Unit 4: Electron Configuration Homework - Catch up on work even if it’s LATE!

4. © 1998 by Harcourt Brace & Company s p d (n-1) f (n-2) 12345671234567 6767 Electron Configuration: The arrangement of electrons in an atom

5. Quantum model states that electrons are found in Orbitals: a 3-D space around the nucleus (“electron cloud”) Electron Orbitals: Electron Configuration: s p d f

6. Orbitals correspond to sublevels on the periodic table Electron Configuration: s d p f Period (Energy level )

7. 1. Aufbau Principle  Electrons occupy the lowest energy orbitals first - “Lazy Tenant Rule”  s  p  d  f Electron Configuration Rules:

8. Orbitals are in order of increasing energy

9. Electron Configuration Rules: 2.Pauli Exclusion Principle:  Each orbital can hold TWO electrons with opposite spins. (Orbital diagram notation)

10. RIGHT WRONG Electron Configuration Rules: 3.Hund’s Rule  Within a sublevel, place one e - per orbital before pairing them.  “Empty Bus Seat Rule”

11. Electron Configuration Energy sublevel Energy Level (Period #) 1s11s1 # of e- in sub level What element? ____________ Hydrogen 1s

12. Electron Configuration 1s 2 What element? ____________ Helium 1s

13. Electron Configuration What element? ____________ Lithium 1s 2 2s 1 1s 2s

14. Electron Configuration What element? ____________ BERYLLIUM 1s 2 2s 2 1s 2s

15. 1s 2 Electron Configuration Phophorus 2s 2 2p 6 3s 2 3p 3

16. O 8e - Orbital Diagram Electron Configuration 1s 2 2s 2 2p 4 Electron Configuration 1s 2s 2p O 8e -

17. © 1998 by Harcourt Brace & Company s p d (n-1) f (n-2)

18. Core vs. Valence Electrons Core electrons: electrons found on the inner energy levels Valence Electrons: electrons found on the outer- most energy level 1s 2 2s 2 2p 6 3s 2 3p 3

19. S 16e - Valence Electrons Core Electrons Mg 12e - 1s 2 2s 2 2p 6 3s 2 3p 4 Core vs. Valence Electrons 1s 2 2s 2 2p 6 3s 2

20. Label the following in your P. table: Noble Gases

21. Noble Gas Notation 1.Write the noble gas of previous row in brackets (Core e - ) 2.Fill in the rest of the configuration (Valence e - ). Ex: Ca 20 e - Cl 17 e - [Ar] 4s 2 [Ne] 3s 2 3p 5

22. Noble Gas Notation (shorthand) S 16e - Valence Electrons Core Electrons S16e - [Ne] 1s 2 2s 2 2p 6 3s 2 3p 4 Noble Gas Notation Regular Notation (longhand) 3s 2 3p 4

23. Ion Notation Ion- atom with a charge because of a gain or lose valence electrons to become more stable. Noble Gases are already stable Other atoms will try to be like the Noble Gases

24. Label the following in your P. table: Noble Gases

25. O 2- Ion Notation O 8e - 1s 2 2s 2 2p 4 O 2- 10e - 1s 2 2s 2 2p 6 10e - [He] 2s 2 2p 6 O 2- = Ne

26. Ion Notation Fe Fe 2+ Fe 3+ 26 e- 24 e- 23 e- 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 6 1s 2 2s 2 2p 6 3s 2 3p 6 3d 6 1s 2 2s 2 2p 6 3s 2 3p 6 3d 5 Fe (II) Fe (III)

27. Why do the elements in the f-block sit below the rest of the Periodic table? So it can fit better on one page!

28. © 1998 by Harcourt Brace & Company s p d (n-1) f (n-2)