Solubility and its types in detail

2. Solutions
 Solution – a homogeneous mixture of
pure substances
 The SOLVENT is the medium in which the
SOLUTES are dissolved. (The solvent is
usually the most abundant substance.)
– Example:
• Solution: Salt Water
• Solute: Salt
• Solvent: Water

3. READ ONLY SECTION:
 HOW DO SUBSTANCES DISSOLVE?
– “According to the kinetic theory, the water
molecules in each glass of tea are always
moving. Some moving water molecules
collide with sugar crystals. When this
happens, energy is transferred to the sugar
molecules at the surface of the crystal.”
(Holt, p. 192)

4. The process of dissolution is
favored by:
 A decrease in the energy of the system
(exothermic)
 An increase in the disorder of the
system (entropy)

5. Liquids Dissolving in Liquids
 Liquids that are soluble in one another (“mix”)
are MISCIBLE.
– “LIKE dissolves LIKE”
 POLAR liquids are generally soluble in other
POLAR liquids.
 NONPOLAR liquids are generally soluble in
other NONPOLAR liquids.

6. Factors affecting rate of
dissolution:
 Surface area / particle size
– Greater surface area, faster it dissolves
 Temperature
– Most solids dissolve faster @ higher temps
 Agitation
– Stirring/shaking will speed up dissolution

7. Saturation
 Unsaturated solution – is able to dissolve
more solute
 Saturated solution – has dissolved the
maximum amount of solute
 Supersaturated solution – has dissolved
excess solute (at a higher temperature).
Solid crystals generally form when this
solution is cooled.

8. SOLUBILITY
 Solubility = the amount of solute that will
dissolve in a given amount of solvent

9. Factors Affecting Solubility
 The nature of the solute and solvent:
different substances have different solubilities
 Temperature: many solids substances
become more soluble as the temp of a
solvent increases; however, gases are less
soluble in liquids at higher temps.
 Pressure: Only affects the solubility of gases.
As pressure increases, the solubility of gases
increases.