1. DO NOW… Draw the diagram that reminds you of the correct order of electron orbitals. Write out the electron configuration for Pd in full form and in noble gas notation Homework = Read 5.3 AGAIN & #’s 16-18,21,42,44-47

2. So how am I supposed to remember the order of the rooms? 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 6 5s 2 4d 8 46 total e - Pd orbitals? Noble Gas Notation = [Ar] 5s 2 4d 8

3. If e - don’t really stay in hotel rooms… CORRECT VOCABULARY Floor = Principal Energy Level Suite = Sublevel Room = Orbital 3s 2p 2s 1s 1s 2 2s 1 Li

4. Review....Orbital Shapes

5. Maximum Number of Electrons In Each Sublevel Maximum Number of Electrons In Each Suite Type Suite # of Maximum # Type rooms of electrons s 1 2 p 3 6 d 5 10 f 7 14 Sublevel orbitals

6. Excitation of Hydrogen Atoms

7. Return to Ground State

8. An Excited Lithium Atom Photon of red light emitted Li atom in lower energy state Excited Li atom Energy

9. Chemist Humor Question: Why does hamburger have lower energy than steak? Answer: Because it’s in the ground state.

10. The Electromagnetic Spectrum (BIG FANCY WORDS FOR.... LIGHT)

11. Visible part of EM SPectrum PRISM Slit Ray of White Light Waves 1 / 33,000 ” long Waves 1 / 70,000 ” long R ed O range Y ellow G reen B lue I ndigo V iolet 400 nm – 700 nm

12. BIG topics...copy these down  Light (electromagnetic radiation)  particle/wave dual nature of light  c, λ, ט, E & h  Quantum vs. Photon (p. 128, p.144)  Quantum theory (wave mechanical model)  Bohr model of atom (ENERGY LEVELS)  Atomic absorption/emission & spectra  Orbital shapes & Heisenberg uncertainty  Electron configurations  orbital, e - configuration  noble gas notation  Aufbau, Pauli, & Hund

13. Waves  Wavelength ( ) - length of one complete wave. Common units: m or nm  Frequency ( ) - # of waves that pass a point during a certain time period (usually per second) Common Units: hertz (Hz) = 1/s = s -1  Amplitude (A) - distance from the origin to the trough or crest (height of one wave) Courtesy Christy Johannesson www.nisd.net/communicationsarts/pages/chem

14. Frequency O’Connor, Davis, MacNab, McClellan, CHEMISTRY Experiments and Principles  1982, page 166 1 second Frequency 4 cycles/second = 4 hertz 12 cycles/second = 12 hertz 36 cycles/second = 36 hertz

15. Vocabulary of a Wave Zumdahl, Zumdahl, DeCoste, World of Chemistry  2002, page 324 A c = speed of light = 2.998 x 10 8 m/s (really fast, true for every kind of light!)

16. Wave-Particle Duality JJ Thomson won the Nobel prize for describing the electron as a particle. His son, George Thomson won the Nobel prize for describing the wave-like nature of the electron. The electron is a particle ! The electron is an energy wave!

17. The Wave-like Electron Louis deBroglie The electron propagates through space as an energy wave. To understand the atom, one must understand the behavior of electromagnetic waves.

18. Quantum Theory Max Planck (1900) ‏  Observed - emission of light from hot objects  Concluded - energy is emitted in small, specific amounts (quanta) ‏  Quantum - minimum amount of energy gained or lost by an atom Courtesy Christy Johannesson www.nisd.net/communicationsarts/pages/chem

19. Electromagnetic Radiation = PHOTONS Light as a wave Light as a stream of energy (packets of photons) Zumdahl, Zumdahl, DeCoste, World of Chemistry  2002, page 325

20. IMPORTANT LIGHT EQUATION #1  Frequency & wavelength are inversely proportional c = c:speed of light (2.998  10 8 m/s) :wavelength (m, nm, etc.) :frequency (Hz or s -1 ) Courtesy Christy Johannesson www.nisd.net/communicationsarts/pages/chem

21. Example Problem for Equation #1 Find the frequency in Hertz of microwave radiation with a wavelength of 7.5  10 -3 m. GIVEN: = ? = 7.5  10 -3 m c = 2.998  10 8 m/s WORK: = c  = 2.998  10 8 m/s 7.5  10 -3 m = 4.0 x 10 10 s-1 = 4.0 x 10 10 Hz Courtesy Christy Johannesson www.nisd.net/communicationsarts/pages/chem

22. IMPORTANT LIGHT EQUATION #2 E:energy (J, joules) h:Planck’s constant (6.6262  10 -34 J·s) :frequency (Hz) E = h The energy of a photon is proportional to its frequency. Courtesy Christy Johannesson www.nisd.net/communicationsarts/pages/chem

23. Energy of Waves – It takes more energy to travel at a higher frequency… Low frequency High frequency, short wavelength Amplitude Low frequency, long wavelength short wavelength 

24. Red and Blue Light Zumdahl, Zumdahl, DeCoste, World of Chemistry  2002, page 325 Photons - particle of light that carries a quantum of energy

25. Example problem for Equation #2 Find the energy of a red photon with a frequency of 4.57  10 14 Hz. GIVEN: E = ? = 4.57  10 14 Hz h = 6.6262  10 -34 J· s WORK: E = h E = ( 6.6262  10 -34 J· s ) ( 4.57  10 14 Hz ) E = 3.03  10 -19 J Courtesy Christy Johannesson www.nisd.net/communicationsarts/pages/chem

26. Example problem using BOTH Equations… Find the energy of a photon with a wavelength of 1.0 x 10 -3 nm. GIVEN: h  x 10 -34 J s c = 3.00 x 10 8 m/s = ? = 1.0 x 10 -3 nm = ???? m WORK: = c = 3.00  10 8 m/s 1.0 x 10 -12 m = 3.0 x 10 20 s -1 E = hv c = λv  = (6.626 x 10 -34 J s)(3.0 x 10 20 s -1 ) E = 1.99 x 10 -13 J

27. Equations with Wavelength and Frequency E = h c =  c = speed of light (2.998 x 10 8 m/s)‏ = frequency (s -1 )‏  = wavelength (m)‏ E = energy (Joules or J)‏ h  = Planck’s constant (6.626 x10 -34 J s)‏ = frequency (s -1 )‏ “nu” “lamda” Highest energy Moderate energy Lowest energy

28. Common wavelength units for electromagnetic radiation Picometer pm 10 -12 Gamma ray Ångstrom Å 10 -10 X-ray Nanometer nm 10 -9 X-ray Micrometer  m 10 -6 Infrared Millimeter mm 10 -3 Infrared Centimeter cm 10 -2 Microwave Meter m 10 0 Radio Unit Symbol Wavelength, (m) Type of Radiation Copyright © 2007 Pearson Benjamin Cummings. All rights reserved.

29. Bohr Model of Hydrogen Nucleus Possible electron orbits e Great theory, BUT it turned out to be totally wrong!! Next week we’ll see a better theory Further away from nucleus means higher energy level…

30. Bohr Model electrons exist only in orbits with specific amounts of energy called energy levels Therefore… electrons can only gain or lose certain amounts of energy only certain photons are produced Courtesy Christy Johannesson www.nisd.net/communicationsarts/pages/chem

31. Continuous and Line Spectra light Na H Ca Hg 400 450 500 550 600 650 700 750 nm Visible spectrum  (nm)

32. Flame Test Emission Spectra Photographs of flame tests of burning wooden splints soaked in different salts. methane gas wooden splintstrontium ioncopper ionsodium ion calcium ion

33. Copyright © 2006 Pearson Benjamin Cummings. All rights reserved.

34. Example: Emission Spectrum of Hydrogen 1 nm = 1 x 10 -9 m = “a billionth of a meter” 410 nm434 nm486 nm656 nm ATOMIC SPECTRA: See p. 141 before Friday!

35. Other Elements  Each element has a unique bright-line emission spectrum. i.e. “Atomic Fingerprint” Helium zBohr’s calculations only worked for hydrogen!  Courtesy Christy Johannesson www.nisd.net/communicationsarts/pages/chem

36. e-e- e-e- Ground state Excited state Electrons can only be at specific energy levels, NOT between levels.

37. Continuous vs. Quantized Energy Energy A B continuous quantized A continuous B quantized

38. Bohr Model  Energy of photon depends on the difference in energy levels  Bohr’s calculated energies matched the IR, visible, and UV lines for the H atom 1 2 3 4 5 6 Courtesy Christy Johannesson www.nisd.net/communicationsarts/pages/chem nucleus

39. Frequency A Frequency B Frequency C n = 2 n = 1 n = 3 A B C A + B = C

40. DO NOW: Draw this diagram in your notes and take out your HW from Mon & Tues.

41. DO NOW: Draw this diagram in your notes & take out HW

45. Copyright © 2007 Pearson Benjamin Cummings. All rights reserved.