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Review sessions
Saturday (11/23), 11:00 am, in CP-145
Sunday (11/24), 10:00 am, in CP-145
Exam Tuesday, 11/26 8:30pm to 10:30pm, AHC3-Room 110
Coverage
Chapter 6
6.4 to 6.9
Chapter 7
ALL
Chapter 8
ALL
Chapter 9
ALL
Chapter 10
ALL
Chapter 6
Quantum numbers, restrictions, meaning
Electron configurations for atoms (long and short method)
Filling order for orbitals
Pauli principle
Aufbau principle
Hund’s rule
Orbital filling diagrams
Anomolous electron configurations (d4, d9)
Quantum Numbers
The quantum numbers and their possible values are as follows.
n = 1, 2, 3, …
Principal quantum number. Determines the
energy, the average distance between the
electron and the nucleus, and orbital size.
Angular momentum quantum number.
Determines the shape of the electron cloud
(orbital shape s ( = 0) d ( = 2)
p ( = 1) f ( = 3)
Magnetic quantum number. Determines the
m  = 0, 1, 2, …,  
orientation of the orbital.
 = 0, 1, …, (n-1)
ms =  1/2
Spin quantum number. Determines the
orientation of the electron spin.
Mnemonic Device For Energy Ordering
We may use the following mnemonic device for the order in
energy of the orbitals. The order in which the labels are crossed out
below is the order of energies. Maximum # electrons 2 (for s orbital), 6
(for set of p orbitals), 10 (for set of d orbitals), etc.
1s
2s
2p
3s
3p
3d
4s
4p
4d
4f
5s
5p
5d
5f …
6s
6p
6d
6f …
Anomalous Electron Configurations
The rules we have given for predicting electron configurations for
atoms work most of the time. However, there are occasional cases where
the actual electron configuration is different from the predicted
configuration.
Element
Predicted
Actual
Cr (24 e-)
[Ar] 4s2 3d4
[Ar] 4s1 3d5
Mo (42 e-)
[Kr] 5s2 4d4
[Kr] 5s1 4d5
Cu (29 e-)
[Ar] 4s2 3d9
[Ar] 4s1 3d10
Ag (47 e-)
[Kr] 5s2 4d9
[Kr] 5s1 4d10
Chapter 7
Electron configurations and common ions for main group
elements
Electron configurations for cations (period 4 and below)
Trends
sizes of atoms
sizes of ions
1st ionization energy
metallic character
electronegativity
Chapter 8
Ionic bonding; Lewis structures for ions; trends in lattice energy
Covalent bonding – Lewis structures when octet rule is obeyed
Polar bonds and polar molecules
Resonance structures and formal charge
Exceptions to octet rule
less than an octet
odd number of electrons
expanded octet
Average bond enthalpy and its use
Chapter 9
VSEPR theory
counting electron containing regions
electron (cloud) geometry and molecular geometry
Common geometries and bond angles
Hybrid orbitals and relationship to # electron containing regions
Sigma and pi bonds
MO theory, bonding and antibonding Mos, bond order, etc.
electron cloud hybridization electron cloud
regions
geometry
molecular geometry
(# bonds)
2
sp
linear
linear (2)
3
sp2
trig. planar
trig. planar (3); nonlinear (2)
4
sp3
tetrahedral
tetrahedral (4); trig. pyramid (3);
nonlinear (2)
5
sp3d
trig. bipyramid
trig. bipyramid (5); see-saw (4);
t-shape (3); linear (2)
6
sp3d2
octahedral
octahedral (6); square pyramid (5);
square planar (4)
Chapter 10
The ideal gas law and its use (pV = nRT)
Dalton’s law of partial pressures (pi = Xi ptotal)
Kinetic theory, average speed of molecules (urms = [3RT/M]1/2)
van der Waals equation p = nRT - an2
(V – nb) V2
Problems
If  = 1
What kind of orbital do you have?
What are the possible values for m?
Give the electron configuration for the following
P, Br, Cu, O2-, Pd2+
From the atoms Mg, Sr, S, Te
Which atom is largest? Which atom is smallest?
Which atom has the largest 1st ionization energy?
Which element is most metallic?
Problems
Give Lewis structures, electron geometry, molecular geometry, and
hybridization for the following
OCS, NH4+, CH3CHO (both C atoms)
SF4, XeCl2
A gas sample is a mixture of two gases, Ar and CO2, with XAr = 0.43.
The temperature and pressure of the gas are T = 320. K and p = 845. torr.
How many grams of argon and how many grams of CO2 are there in
1.000 L of the gas mixture?