SOLUTIONS
What is a solution?
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A mixture that has the same composition throughout
Also known as a homogenous mixture
Made of solutes and solvent
Parts of a Solution
Solvent

The substance that is
doing the dissolving
Solute

The substance being
dissolved

Solid dissolving in a liquid
 Solid
– solute
 Liquid – solvent

Liquid dissolving in a liquid
 Liquid
in a larger amount - solvent
Water – Universal Solvent
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Water has a positive end and a negative end.
The positive end is attracted to our negative end.
Water molecules pull apart the solute and then they
mix evenly, forming a solution.
Just remember –
 LIKE
DISSOLVES LIKE!
Dissolving Solutes

To speed up a solution:
 Stirring
 Brings
 Smaller
more fresh solvent in direct contact with the solute
crystal size
 Increases
the surface area which allows more solvent to
come in contact with the solute
 Increasing
 The
temperature
speed of the solvent increases and causes them to bump
into the solute
 Solute particles come loose and dissolve faster
Solubility
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The maximum amount of solute that can be
dissolved in a given amount of solvent at a given
temperature
Measured in grams per 100 g of water
Depends on the nature of the substances
Concentration
• large amount of
Concentrated solute is dissolved
in the solvent
Dilute
• small amount of
solute is dissolved
in the solvent
Concentration
Types of Solutions
Unsaturated
Saturated
Supersaturated
• A solution that can dissolve more solute at a given
temperature
• A solution that contains all the solute it can hold at a
given temperature
• More solute can be added if heat is applied to the
solution
• A solution that contains more solute that a saturated
solution at the same temperature
• Solute tends to collect at the bottom
Solubility Curves
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Each line represents a particular substance.
Shows type of solution
 Above
the line – supersaturated
 On the line – saturated
 Below the line - unsaturated

Graph
 Independent
variable – Temperature in Celsius
 Dependent variable – grams per 100 g of water
Solubility Curves
Effects of Solute Particles

Adding a solute to a solvent lowers the freezing
point of the solvent.
 Example

– antifreeze
Increasing the boiling point depends on the number
of solute particles in the solvent
Questions