1. Energy Unit
Energy of an Electron

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

3. 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!

4. Electromagnetic Radiation:
Energy that moves through space and matter both in the form of magnetic and electric waves and in the form of a stream of particles.

5. Waves Amplitude = height of wave Trough = the lowest point of a wave.
Waves are described by their amplitude, wavelength, crest, and troughs.
Amplitude = height of wave
Trough = the lowest point of a wave.
Crest = the highest point of a wave.

6. Wave Characteristics Wavelength Frequency
The distance between two consecutive wave peaks.
Frequency
How many wave peaks pass a certain point per given time period.

7. Photons
Stream of tiny packets of energy… LIGHT

8. Electromagnetic radiation propagates through space as a wave moving at the speed of light. -speed of light is 3.0 x 108 m/s

9. The energy (E ) of electromagnetic radiation is directly proportional to the frequency () of the radiation.

10. Different wavelengths of electromagnetic radiation carry different amounts of energy.
Red light carries less energy than blue light.
The longer the wavelength of light, the lower the energy of its photons.
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11. Long Wavelength = Low Frequency = Low ENERGY
Short Wavelength= High Frequency = High ENERGY

12. fireworks
Fireworks use the emission of photons to display the fantastic colors.

13. Photon Emission

14. Remember that different wavelengths of light carry different amounts of energy per photon.
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15. The energy is said to be emitted in “discrete” amounts
Only certain types of photons are produced...we don’t see all colors only selected colors.
The energy is said to be emitted in “discrete” amounts
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16. Atoms have certain discrete energy levels. energy levels are quantized
Atoms have certain discrete energy levels...energy levels are quantized...only certain values are allowed.
More like fig. b
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17. Spectroscopic analysis of the visible spectrum…
…produces all of the colors in a continuous spectrum

18. Spectroscopic analysis of the hydrogen spectrum…
…produces a “bright line” spectrum

20. Element Spectra