• Light emission from electrons are from higher to lower energy states
• Each atom has a diffrent # of valence electrons
• Can only have certain energies (called quantumn states)
• Excitation
  • electron has a greater electric potential energy farther from nucleus
  • when electron moves to other level, it gets excited
  • When an electron releases energy (photons/light) it lowers by a level
  • Photon freqency == energy released
  • $$ E = hf$$
  • h is planks constant
  • can use this to identify an element
• Emission Spectra
  • absorpsion == gain energy
    • what did electron gain to change state
    • Push white light through substance, and see what it takes to excite
  • emission == lose energy
    • what did it lose to change
    • Give lots of energy (will drop)
    • The take that light through a diffraction grate (prism)
    • then you'll see the lights emitted