atomic spectra
to understand H spectrum need Quantum Mechanics
- electrons orbit the nucleus like planets orbit the sun
- lower orbits have lower energies
- decay of satellite orbits with air drag present
- H atom should emit a continuous spectrum
- it’s continuously accelerating
- Only certain orbits “allowed” by QM
- when the angular momentum is an integral multiple of h/2?
- change between “allowed” orbits results in a photon
- conservation of energy
- energy of photon (= hf) equals difference in energy
- example: allowed orbits of H atom
- lowest Energy level (1) preferred
- If atom is excited into 3rd level, it will decay back to 1
- decay 3 -> 2 produces red line of H (H-alpha)
- 4 -> 2 produces blue line of H (H-beta)