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 6Quantum 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 NumbersThe quantum numbers and their possible values are as follows.

n = 1, 2, 3, …

= 0, 1, …, (n-1)

m = 0, 1, 2, …,

ms = 1/2

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 orientation of the orbital.

Spin quantum number. Determines the orientation of the electron spin.

Mnemonic Device For Energy OrderingWe 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 …

So 1s < 2s < 2p < 3s < 3p < 4s < 3d < 4p < 5s < 4d < 5p < 6s < 4f ...

Anomalous Electron ConfigurationsThe 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 7Electron 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 8Ionic 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 9VSEPR 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 molecular geometry regions 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 10The 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

ProblemsIf = 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?

ProblemsGive 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?