1. TOIPC: EMISSION SPECTRUM

2. Flame Test DEMO

3. When Matter is heated it gives off light –Example: fire work, pyrotechnics, flame test –The heat energy absorbed by the metal ions excites the atoms’ electrons –The absorbed energy is eventually released in the form of light

4. Another example –Example: light bulb –The electrical energy absorbed by the filament excites the atoms’ electrons –The absorbed energy is eventually released in the form of light

5. Why do we see colors? Where do they come from? What are they?

6. CONTINUOUS (WHITE LIGHT) SPECTRA When normal white light (such as light from the sun or a light bulb) is passed through a prism (or rain drop), the light separates into a continuous spectrum of colors

7. PRISM White light is broken into 7 spectral lights, what are they? ROY G BIV

8. Originally Scientists (even Newton) thought that light was made up of particles but this couldn’t’ explain why different color were refracted different NOTICE: Violet bends a lot more than Red

9. Light made up of waves

10. Basic Wave Vocab

11. Transverse vs Longitudinal Waves Transverse Longitudinal

12. Wavelength vs. Frequency WAVELENGTH = distance light travels to complete 1 cycle FREQUENCY = number of cycles completed in 1 second

13. The colors we see have different wave lengths Red = longer wave length Violet = shorter wave length Which one has the higher frequency?,higher frequency,lower frequency Wavelength and Frequency have an inverse relationship

14. You can even calc. the Wave Velocity speed of wave in direction is traveling Velocity = wavelength x frequency Velocity =

15. Scientists realized that many light waves couldn’t been seen with the naked Electromagnetic Spectrum

16. Higher EnergyLower Energy LINK

17. THE MYSTERY OF EMISSION- LINE SPECTRUM Solids, liquids, and dense gases emit light of all wavelengths, without any gaps = Continuous Spectrum

18. Thin gases emit light of only a few wavelengths = Emissions or Bright Line Spectrum

19. Bright Line Spectrum Atoms cannot emit energy continuously, rather they emit energy in precise quantities How does this work –Electrons absorb energy (they get EXCITED) and “jump” to a higher energy level –After a short time, they “fall” back to lower energy level, giving off a specific amount of energy (a quantum of energy) in the form of a photon (light)

20. Scientists of the 19 th century quickly figured out that each element generates its own unique set of wavelengths of emissions and absorptions due to it’s unique electron configuration. Hydrogen:

21. Neon line spectra