Download Steps Toward Quantum Theory I. Quantized Energy Levels 1. Heat

Steps Toward Quantum Theory
I. Quantized Energy Levels
1. Heat Capacity less than predicted: Failure of Equipartition Theory
2. Blackbody Radiation Spectrum: p = h/h = 6.6261x10-34 J s
 = h/mev
1
1
1
1




~
3. Atomic and Molecular Spectra:  = h n2 – n2 = 109677.5 cm-1 n2 – n2
f
i
f
i




II. Quantum Nature of Light
1. Photoelectric Effect: E = h
h- = h/2 = 1.0546 x 10-34 J s
2. Compton Effect: p = h/c or p=h/
c = x m s-1
III. Structure of the Atom
1. Cathode Rays: Thomson (e/m), Mulliken (e)
2. Nucleus, Rutherford Scattering
3. Canal Rays, Goldstein
4. Electronic Structure: Bohr : circumference = integer number of wavelengths : 2r = n
mevr = nħ
e4me Z2
1
En = –
=
–



h  2
2
n 
3222o h-2  n 
1 1
E = h = h n2 – n2
i
 f
4πeoh- 2
radius of first Bohr orbit = ao= m e2 = 0.529 Å
e
e = 1.60218x10-19C
me = 9.1093897x10-31 kg
o = 8.85419 x 10-12 J-1 c2 m-1
IV. Wave Nature of Particles
1. de Broglie Relationship, E = h = mc2 , p = h/
2. Diffraction of Electrons: Davisson and Germer, p = h/
3. Diffraction of Protons and Neutrons
d

d
 dcos 
Colby College
 dcos 
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