1. Warm-Up
What and 3 sources of error in the flame test lab? (Don’t just say “we messed up.” Consider how you could have done things better or how the equipment interfered with your results)

2. Measuring Light Energy
Friday 11/15/13

3. Flame Tests
Many elements give off characteristic light which can be used to help identify them.
strontium
sodium
lithium
potassium
copper

4. Electron transitions can occur from multiple principle energy levels
This produces bands
of light with definite wavelengths.

5. Characteristics of Light
We can determine the value of two characteristics of light: wavelength and frequency

6. Wave Equation #1
Speed of light= 3.00x108 m/s

7. Example
The wavelength of green light is about 5.22x10-7 m. What is the frequency of this radiation?

8. Example
The wavelength of green light is about 5.22x10-7 m. What is the frequency of this radiation?

9. Planck Equation
Max Planck realized that frequency is not only related to wavelength, but also the energy of a wave.
Plank Equation:

10. Remember…
Frequency can be rewritten as

11. Example
What is the energy of a photon (light particle) with a wavelength of 8.27x10-7 m? What type of radiation is it?

12. Your Job
Calculate the energy values from the last two problems on the Flame Test Lab & turn in.
Work on the Light and Energy Problems. You will use today’s and Wednesday’s notes.