Summary

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Summary

• Nuclear Chem
• Particles, energy, mass defect ? ?E ?mc2
• nuclear processes kinetic energy determination
• Nuclear stability, binding energy, thermo vs.
  kinetic
• nuclear decay kinetics
• neutron activation
• 2. Wave Particle Duality electrons and photons
• Interference need for wave functions (?)
• H.U.P. probability densities (?2)
• quantized energies (matter/Planck
  light/Einstein)
• de Broglie wavelengths Results
• 3. H atom
• Line Spectrum Bohr atom
• quantized energy lowest energy
• En -(Z2/n2)R y R y 2.178 x 10-18 J
• ?EEn2 En1
• quantized angular momentum Summary
• Correct physics q.m. and Schroedinger Eq.

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? (wave function called orbital for atom)
f(r,?,?) Rn,l(r)Yl,m(?,?) n (1,2,3,) energy
and size l (0,1,2,,n-1) shape (s,p,d,f,) ml
(0,1, 2, , l) direction (nothing,x,xy,) Ra
dial nodes (n- l -1), size of atoms (90
contours) Angular l nodes, angular
dependence E f(n) only for H atom
(electron/nucleus attraction only) 4.
Multielectron Atoms electron/nucleus
electron/electron spin! ms Pauli Exclusion
Principle E(s)ltE(p)ltE(d) (penetration of radial
function) orbital energy diagram Auf Bau to get
lowest energy electron configuration shell,
core, valence ground state, excited states, ions

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• Periodic Table
• Explained by Atomic Q.M. Auf Bau using Pauli
  and Hund
• periods explained by same n
• groups explained by same of valence electrons
• Representative Elements (s p electrons)
  metals, non-metals, metalloids
• Transition metals (d f electrons)
• ns before (n-1)d
• Transition metal ions
• - ns removed before (n-1)d
• paramagnetism diamagnetism
• noble gases filled shell

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Decay processes Beta emission n ? p
e- ? (neutron rich) Positron emission p ?
n e ? (neutron poor) Electron
capture (AZEl e-) ? AZ-1El ? (proton
rich) Alpha emission AZEl ? 42He A-
4Z-2El (heavy elements)
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1) Nuclear Equations a) Z and A must balance
b) ?m ? 0 !!!
147N ? ? 146C
11H
Z7, A14 Z7, A15 ?
10n
147N 10n ? 146C 11H balanced


2) Binding energy of nuclei from ?m Nuclear
Stability ?Erxn ?m co2 8 11H 8 10n
? 168O ?m m(168O) - 8m(11H) -
8m(10n) - 0.13700 u lt 0 !! so
168O is more stable - 0.13700 u
(931.494 MeV / u) - 127.62 MeV ?Erxn
Binding Energy Eb(168O) - ?Erxn 127.62
MeV For comparison Binding Energy/nucleon
Eb/A 127.62/16 7.976
MeV/nucleon
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Activity (A) dN/dt N A/k amount
proportional

to activity Kinetics A Ai e-kt
ln(A) -kt ln(Ai) k rate
constant (ln 2)/t1/2
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• Previous results must be
• applied to atoms
• Interference Electron must be described by
• wave-type
  mathematical function
• 2) HUP Electron position described by
  probability
• (cant know position exactly
• if know momentum)
• 3) Quantized Energy in matter and light

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Energy Levels and Transitions of H atom En
-(1/n2)Ry n 1, 2, 3,
H atom H-like atom Quantized
energy levels go as (1/n2) Spectra lines
difference in energy between levels ?En2,n1
-Z2 Ry (1/n22 1/n12) h? (light
energy) H spectra explained!!!
-(Z2/n2)Ry
? E
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Fig. 16-18 Sets of Allowed Quantum s
Orbital symbol ?n,l,m n (l-symbol)direction
Examples ?1,0,0 1s ?2,1,0 2pz Limits
on quantum numbers l ? (n-1) m ? 0, ?1, , ? l
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s orbitals
phases of wave function (?)
Figure 12.18 1s, 2s, 3s orbitals

-
-



90 Probability contours showing relative size of
orbitals
2.6 ao




-
-
12
y
- -
x
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Orbital Energy Diagram
Atom Electron configuration H 1s
He 1s2
unpaired electron magnetic atom!!
Li 1s22s
Be 1s22s2
B 1s22s22p
Also magnetic
C 1s22s22p2
Minimize e- - e- repulsion dont pair spins in
degenerate orbitals unless you must Hunds rule
Auf Bau (Building up) principle To get ground
state electronic configuration 1) put e-s in
lowest energy orbital, 2) obey Pauli principle 3)
obey Hunds rule
N 1s22s22p3 O 1s22s22p4 F 1s22s22p5 Ne 1s22s22p6
Can do ions O2- 1s22s22p6 excited
states Na Ne6s
Na 1s22s22p6 3s Mg 1s22s22p6 3s2