1. I. Waves & Particles (p. 97-100) Ch. 4 - Electrons in Atoms

2. A. Waves zWavelength ( ) - length of one complete wave zFrequency ( ) - # of waves that pass a point during a certain time period yhertz (Hz) = 1/s zAmplitude (A) - distance from the origin to the trough or crest

3. A. Waves A greater amplitude (intensity) greater frequency (color) crest origin trough A

4. B. EM Spectrum LOWENERGYLOWENERGY HIGHENERGYHIGHENERGY

5. LOWENERGYLOWENERGY HIGHENERGYHIGHENERGY ROYG.BIV redorangeyellowgreenblueindigoviolet

6. B. EM Spectrum zFrequency & wavelength are inversely proportional c = c:speed of light (3.00  10 8 m/s) :wavelength (m, nm, etc.) :frequency (Hz)

7. B. EM Spectrum GIVEN: = ? = 434 nm = 4.34  10 -7 m c = 3.00  10 8 m/s WORK : = c = 3.00  10 8 m/s 4.34  10 -7 m = 6.91  10 14 Hz zEX: Find the frequency of a photon with a wavelength of 434 nm.

8. C. Quantum Theory zPlanck (1900) yObserved - emission of light from hot objects yConcluded - energy is emitted in small, specific amounts (quanta) yQuantum - minimum amount of energy change

9. C. Quantum Theory zPlanck (1900) vs. Classical TheoryQuantum Theory

10. C. Quantum Theory zEinstein (1905) yObserved - photoelectric effect

11. C. Quantum Theory zEinstein (1905) yConcluded - light has properties of both waves and particles “wave-particle duality” yPhoton - particle of light that carries a quantum of energy

12. C. Quantum Theory E:energy (J, joules) h:Planck’s constant (6.6262  10 -34 J·s) :frequency (Hz) E = h zThe energy of a photon is proportional to its frequency.

13. C. Quantum Theory 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 zEX: Find the energy of a red photon with a frequency of 4.57  10 14 Hz.