You have already discussed the phase properties of liquid
crystals, which seem somehow 'modern' and novel. Some of the properties
of amphiphilic molecules have been known for centuries such as the effect
of soap an solubility.
The energetics of the dissolution of Ionic Salts to for Electrolytes is particularly interesting because the LATTICE energy and HYDRATION energies are both very high, but sometimes almost exactly cancel out.
KSP = [M+ (aq)]e[X-(aq)]e
The temperature dependence of the solubility product is
that of any other equilibrium constant, and depends on the sign and magnitude
of the enthalpy change for the transformation.
The Gibb's Helmholtz eqn :
\The van't Hoff eqn:
Gases dissolve in liquids (and solids), but have much simpler behavior than eleectrolytes. For example, gases are less soluble at high temperature than at low temperature. (What does this say about the enthalpy of dissolution of a typical gas in a liquid?) Does a gas dissolved in a liquid behave as an ideal mixture?
This is a 'special case' of Henry's Law, an empiricle relation that is best applied to dilute solutions.
pi = kH Xi
So Raoult' Law says:
The addition of solute RAISES the boiling point of a solvent
The addition of solute LOWERS the freezing point of a
(Why molality?? Because it really should be mole fraction, but Molarity depends too much upon the change in volume upon mixing)
The pressure required to allow for no transport of solvent across the membrane is called the OSMOTIC pressure and obeys the relation:
Osmotic pressure has a great effect on living CELLS, because their walls are a semipermeable membrane.
(a) crenation is caused by water movement out of
a cell in a hypertonic solution.
(b) hemolysis is caused by water movement into a cell in a hypotonic solution.