2. Why are electrons restricted to specific energy levels or quantized? Louis de Broglie – proposed that if waves have particle properties, possible particles have wave properties.This includes such things as nodes:

3. Relationship between wave properties (wavelength) and particles (mass*volume) De Broglie equation λ = h / mu wavelength, planks, mass, velocity

4. Problem on Page 260 Calculate the wavelength of a H atom, mass = 1.674 x 10 -27 kg moving at 700 cm/s

5. Quantum Mechanics Heisenberg Uncertainty Principle – It is not possible to know simultaneously both the momentum p (mass x velocity) and the position of a particle with certainty This is due to the measurement methods moving the electron

6. Quantum Mechanics ΔxΔp ≥ h / 4π If our measurement of the momentum p is increased, knowledge of position decreases If the measure of position x is known more precise, the momentum measurement is decreased One problem is due to the electrons not following circular paths like planets.

7. Schrödinger Equation

8. This works fair for the Hydrogen atom We approximate multi electron atoms

9. Quantum Numbers n – principle quantum number Energy level of an orbital = 1, 2, 3…

10. Quantum Numbers l – Angular momentum number (Orbital) l = n-1 0-s 1-p 2-d 3-f

11. Quantum Numbers ml – Magnetic Quantum number the number of them = (2l + 1), If l = 0 then ml = is 0 If l = 1 then ml = 1,0,-1 ; Describes the orientation in space x y z

12. Quantum Numbers Ms –electron spin quantum number = ½ or –½

13. Quantum Numbers Ms –electron spin quantum number = ½ or –½