electromagnetic radiation - aka radiant energy  

• visible light is a type of electronmagnetic radiation
• speed of light = 3.00 x 108 m/s
• wavelength - distance between successive peaks/troughs
• frequency - # of complete wavelengths/cycles that pass a point per second
• amplitude - intensity of radiation; max height of wave
• (frequency)(wavelength) = speed of light = c = nl
  • frequency = n
  • wavelength = l
• smaller wavelength >> higher frequency >> more powerful radiation

Planck's constant - 6.63 x 10-34 J-s  

• quantum - "fixed amount;" smallest quantity of energy that can be emitted/absorbed
• energy always emitted in chunks of minimum size
• energy = Planck's constant x frequency
  • E = hn
• energy quantized, can only increase in steps (though steps are extremely small)
• photoelectric effect - photons striking metals cause electrons to be emitted
  • photon - energy packet, transfers energy to electrons
  • energy of photon = E = hn
• 6.02 x 1023 photons per mol

Find energy of 1 photon light w/ wavelength 589 nm  

• c = nl
• 3.00 x 108 m/s = n(589 nm)
• n = (3.00 x 108 m/s) / (5.89 x 10-7 m) = 5.09 x 1014 s-1
• E = hn
• E = (6.63 x 10-34 J-s)(5.09 x 1014 s-1) = 3.37 x 10-19 J/photon