by: ann marie baker
Using Plank's constant, Bohr obtained an accurate formula for the energy levels of the hydrogen atom. He said that the angular momentum of the electron is quantized- meaning, it can have only discrete values. He assumed that otherwise electrons obey the laws of regular mechanics by traveling around the nucleus in circular orbits. Because of the quantization, the electron orbits have fixed sizes and energies. The orbits are labeled by an integer, the quantum number n.