Review of Solutions:
A solution is a mixture of two or more substances in a single
phase. At least two substances must be mixed in order to have
a solution. The substance in the smallest amount and the one
that dissolves or disperses is called the SOLUTE. The substance
in the larger amount is called the SOLVENT. In most common instances
water is the solvent. The gases, liquids, or solids dissolved
in water are the solutes.
The dissolving process involves a consideration of the relative
strength of three intermolecular attractive forces. The type
of forces between solute-solute molecules and solvent-solvent
molecules must be considered. These intermolecular attractions
must be broken before new solute-solvent attractive forces
can become effective. Perhaps the bond breaking and bond forming
processes take place simultaneously.
A solute will dissolve in a solvent if the solute-solvent
forces of attraction are great enough to overcome the solute-solute
and solvent-solvent forces of attraction. A solute will not dissolve
if the solute-solvent forces of attraction are weaker than individual
solute and solvent intermolecular attractions. Generally, if
all three of the intermolecular forces of attraction are roughly
equal, the substances will be soluble in each other.