1. Quantum Mechanics and The Hydrogen Absorption Spectrum

2. Basic Tenant of Quantum Mechanics There exists a wave that defines the probability of finding an electron in space. The amplitude of that wave reflects the probability of finding the wave in that spot.

3. Length of the wave That wave has a characteristic length called the wavelength. The wavelength is the length of one repeating unit.

4. Length and Orbits When that wave is wrapped around a circular atom, the wavelength must line up at the beginning and ending point of the wave. This ensures that when the wave wraps around thousands of times it leads to a bigger wave instead of cancelling itself out

5. Length and Orbits To meet this condition, the circumference of the orbit must be an integer number of wavelengths n = 1 n= 2 n = 3

6. Probability and the wave If this condition is not met, the waves over time will add to 0. This means that the probability of finding an electron in that space will be 0. This means there is 0% chance the electron will be in that space. n = 1.5

7. Electronic Transitions. Electrons transitioning between shells must jump between very specific spots with specific energy levels. This means that the amount of energy given off or absorbed in these transitions is not random but must be the exact energy difference in the electron’s shells.

8. Absorption/Emission Spectrum The photoelectric effect tells us that in each of these processes one photon will be given off or absorbed. The colour of that photon is related to the energy of the photon. This is equal to the energy difference between the shell the electron left and the shell the electron entered. This is why only certain colour appear when electrons move around in atoms in a gas.