1. Unit: Acids, Bases, and Solutions
Introduction to Solutions

2. After today you will be able to…
Explain the differences between the three different types of solutions
Describe how to make a supersaturated solution
Describe how to increase the rate of dissolving

3. A solution is a homogeneous mixture
A solution is a homogeneous mixture. The components are not chemically combined and retain their original properties.
Example: Sugar water – still tastes sweet

4. Solutions A solution is made up of a solute and solvent.
Solute: a dissolved substance
Solvent: the most abundant component of a solution, what does the dissolving

5. Water is called the “universal solvent” because it has the ability to dissolve so many substances.

6. Solutions Recall, aqueous is a solution where water is the solvent.
Example:
NaCl(aq) Na+ + Cl-

7. Solubility 
The maximum amount of solute dissolved in a particular solvent at a specific temperature.
Saturated: No more solute can dissolve
Unsaturated: More solute can dissolve
Supersaturated: More solute is dissolved than theoretically possible

8. To make a supersaturated solution:
Add more solute than solubility allows
Heat the solution up
Slowly cool it down
This is a temporary and unstable state for a solution!

9. Factors that affect solubility:
Temperature: most solid substances have higher solubility as temperature increases
All gas solutes have lower solubility as temperature increases
Pressure: only affects gas solutes
All gas solutes have higher solubility as pressure increases

10. Solubility Curves
For Solid Solutes:
For Gas Solutes:

11. Rate of dissolving: How fast a solute dissolves in a solvent – not to be confused with how much.

12. Rate can be increased by:
Increasing temperature- There is more kinetic energy available to meet the activation energy (energy available for dissolving)
Stirring- Increases the interaction between solute and solvent
Powdering- Increase surface area of the solute which increases the interaction between solute and solvent

13. Liquid-Liquid Solutions
Miscible: two liquids which uniformly mix together (ex: milk and water)
Immiscible: two liquids which will not mix, forms two layers (ex: oil and water)
Non-polar + non-polar = miscible
Polar + Polar = miscible
Non-polar + Polar = immiscible
As a general rule: “Like dissolves like”

14. Concentration
Indicates the amount of solute dissolved in a given quantity of solvent.
Dilute: a small amount of solute
Concentrated: a large amount of solute

15. Questions? Begin WS1