Electrons and Quantum Mechanics - Oakland Schools

12. The 90% probability boundary for an s-orbital is a sphere. For p-orbitals the
boundary is dumbbell shaped. Three p-orbitals, one dumbbell per axis, comprise
a set.
13. In some instances, the behavior of electromagnetic radiation and electrons can
best be understood in terms of wave theory, and in other instances, their
behavior can best be understood if we treat them as discrete particles.
Electromagnetic radiation is usually described in terms of wavelength or
frequency; the quantity most closely associated with particles is mass or
momentum, the mass-velocity product. Louis de Broglie in 1924 offered the
startling proposition that light may sometimes display particle-like characteristics,
and that small particles may sometimes display wavelike properties. He
summarized his proposition in a now famous equation l = h/mv, where l is the
wavelength, h is the Planck constant, m is the mass, and v is the velocity of the
object in question. Wave-particle duality is only important when the wavelength
is of atomic dimensions, i.e., of the order of 10 1 - 10 3 picometers.
14. All we can hope to know about an atomic electron: its energy, angular
momentum, magnetic moment and spin.
15. Anything quantized can be described in terms of separate discrete units. Those
that are continuous are without beginning or end and may be had in any
quantity. Ice cubes are quantized but water flows continuously.
16. Examples: H 1s 1 ; Li 1s 2 2s 1 ; Ga 1s 2 2s 2 2p 6 3s 2 3p 6 3d 10 4s 2 4p 1 63