1. Quantum Atom

2. Problem Bohr model of the atom only successfully predicted the behavior of hydrogen Good start, but needed refinement

3. Heisenberg Uncertainty Principle It is not possible to know both the position and momentum (mv) of an electron Cannot assume that the electron is moving around the nucleus in a well- defined orbit as in the Bohr model

4. Louis de Broglie Suggested matter that is assumed to be of a particle nature, does have wavelike properties Developed an equation for actually calculating this wavelength of matter For very small particles, wavelength is significant

5. Wave Function Erwin Schrodinger developed a series of equations that describe the areas of probability of finding an electron There are different values of these wave functions that occur at different energy levels Wave function are called Orbitals

6. Quantum Mechanics Describes mathematically the properties of an electron Shows regions of probability of finding an electron

7. Quantum Numbers Principal Quantum Number (n) – same as the Bohr energy level Also called shells Range from n=1 to n=7

8. Subshell or Sublevel Angular Momentum Number Come in four types s subshell (spherical) p subshell (dumbbell) d subshell (four lobes) f subshell

9. Orbital Magnetic Quantum Number These are the orbitals (hold 2 e - each) Each sublevel may have more that one orbital with a different orientation in space s ( 1 orbital) p ( 3 orbitals) d (5 orbitals) f (7 orbitals)

11. Main LevelSublevelsNumber of orbitals Electrons in sublevels Total Electrons in Main Level 1s122 2spsp 1313 2626 8 3spdspd 135135 2 6 10 18 4spdfspdf 13571357 2 6 10 14 32

12. Degenerate Orbitals Orbitals that have the same energies

13. Electron Spin Number Electron behaves as if it is spinning on its axis Fourth Quantum number is the spin number

14. Spinning electrons produce magnetic fields

15. Pauli Exclusion Principle No two electrons can have the same set of four quantum numbers If an orbital has two electrons in it, they must have different spins Electrons in the same orbital with different spins are called paired electrons

16. Configuration Arrangement of electrons in the atom Aufbau Principle – orbitals fill in order of increasing energy

17. Orbital Diagram of Li ( 3 e-) 1s 2 2s 1

18. Orbital Diagram of B (5 e-) 1s 2 2s 2 2p 1

19. Hund’s Rule Electrons occupy degenerate orbitals singly first

20. Orbital Diagram of C (6 e-) 1s 2 2s 2 2p 2

21. Orbital Diagram of Ne (10 e-) Configuration 1s 2 2s 2 2p 6

23. Example Determine the configuration of Fe Br

24. Magnetism When electrons in half-filled degenerate orbitals spin in the same direction, the material is magnetic

25. Valence Electrons Outer shell electrons Ones in the last main energy level ▪ K 1s 2 2s 2 2p 6 3s 2 3p 6 4s 1 1 valence e Fe 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 6 2 valence e