You will be required to know the structure of the periodic table.
What is a period and what is a group?
Periods are horizontal rows (numbered 1 through 7)
Groups are vertical columns (numbered 1 through 18)
Some Groups have specific names:
Molecular Orbital Theory Problem Set
1. What is the Born-Oppenheimer approximation?
2. What is the LCAO approximation?
3. Consider the molecule H2. Which of the two molecular orbitals below is bonding? Which is
antibonding? Which should be labeled ? Which
Tetrahedral holes and Octahedral holes
There are two types of holes in a closest-pack system
(you cant fill all of the space!)
Tetrahedral holes are located in the interior of a 4-ball
collection of atoms in the shape of a tetrahedron.
Octahedral holes ar
Some of the most aesthetically pleasing objects in
the world are crystalline structures.
If organic chemistry is the study of carbon compounds, then
inorganic chemistry is the study of the other 117 elements!
(And you thought organic was hard!)
Actually, the boundary between organic and inorganic topics is
Another Way of Determining Crystal Energy
The change in enthalpy for each of these equations may be
K (s) K ( g )
H = 89 kJ/mol
(heat of sublimation)
K ( g ) K ( ) e
H = 425 kJ/mol
We can deter
The energy of a crystal can be obtained by adding together four
components that contribute to the overall energy.
The four components are . . .
1. Energy due to Coulombic attractions and repulsions
between ions (assumes that ions are poin
How do we explain the hiccups?
In general, Zeff increases across the period, so E.A. is expected to
rise. Note the superimposed green slope which represents the
expected rise in E.A. if only Zeff was operati
If the star is more massive still, then temperatures can
continue to rise until an even wider variety of nuclear
reactions becomes feasible.
The net equation:
l is an integer (0,1, . . . , n1) which specifies the angular
Orbitals with different l values have different shapes.
When l = 0, we have an s orbital.
When l = 1, we have a p orbital.
When l = 2, we have a d orbital.
When l = 3, we ha
MO Theory is an attempt to
explain bonding, energy, and other
molecular properties using
Which system is used depends on the author.
This is the simplest represent
By observing the angular component of the wave function, it is
evident that there are additional nodal regions which depend on
For example, in the angular wave function below, Y2pz has a
value of 0 when has a value of 90.
Y2 p z
Nuclear reactions demonstrate that protons and neutrons are
made up of even smaller particles.
The following reactions are known:
It looks as if electrons can come out of the nucl
J. C. Slater proposed several rules for estimating the value of
for any electron.
1. If the electron in question resides in an s or p orbital,
All electrons in principal shells higher than the electron in
question contribute zero to .
The Big Bang
If all of the mass/energy of the universe is confined to a
dimensionless point, an infinite temperature is implied!
Infinite temperature means that all particles have sufficient
kinetic energy to overcome all attractive forces (gra
Van der Waals radius
Defined as the closest that two non-bonded atoms will approach
each other. This is obviously determined in the solid state.
How do you find the closest approach?
Examine every molecule containing the atom in question!
But theres no such thing as a Na2 molecule! What do we do?
We take the distance between adjacent atoms in the metal and
divide by two:
Chemists distinguish between these two types of atomic radii.
They are called covalent radii and m