1. SOLUTIONS

2. Aqueous Solution – a short video
Aqueous - water that contains dissolved substances
Solute Solvent
Dissolved particles Dissolving medium
Being dissolved Doing the dissolving

3. 15.2
Solvents and Solutes

4. 15.2
Solvents and Solutes
If you filter a solution through filter paper, both the solute and the solvent pass through the filter.
A solution cannot be separated by filtration. The small size of the solute particles allows them to pass through filter paper.

5. How Can We Increase Solubility?
16.1
Solution Formation
How Can We Increase Solubility?

6. Stirring and Solution Formation
16.1
Solution Formation
Stirring and Solution Formation
Bring fresh solvent (the water in tea) is continually brought into contact with the surface of the solute (sugar).
More contact with solvent = faster to dissolve (not more to dissolve)

7. Higher temperature = more kinetic energy
16.1
Solution Formation
Temperature and Solution Formation
Higher temperature = more kinetic energy
More kinetic energy = more molecular movement
Equals faster dissolving time and increase in solubility

8. The bigger the molecule the less soluble it is.
16.1
Solution Formation
Particle Size
The bigger the molecule the less soluble it is.
Smaller “pieces” dissolve faster.

9. Solubility is often expressed in grams of solute per 100 g of solvent.
16.1
Solubility
SOLUBILITY
The amount of solute that dissolves in a given quantity of a solvent at a specified temperature and pressure to produce a saturated solution.
Solubility is often expressed in grams of solute per 100 g of solvent.

10. Saturated Unsaturated
Solutions
Saturated Unsaturated
Maximum amount of solute Can hold more solute

11. Factors Affecting Solubility
16.1
Factors Affecting Solubility
A supersaturated solution contains more solute than it can theoretically hold at a given temperature.
The crystallization of a supersaturated solution can be initiated if a very small crystal, called a seed crystal, of the solute is added.
Watch it happen!

12. Rate of dissolving = rate of crystallization A simulation *** pHet Sim
16.1
Solubility
Solution Equilibrium
Rate of dissolving = rate of crystallization
A simulation
*** pHet Sim
In a saturated solution, a state of dynamic equilibrium exists between the solution and the excess solute. The rate of solvation (dissolving) equals the rate of crystallization, so the total amount of dissolved solute remains constant. Inferring What would happen if you added more solute?

13. You have to know molar mass!
16.2
Molarity
Molarity
How do you calculate the molarity of a solution?
Molarity (M) is the number of moles of solute dissolved in one liter of solution.
You have to know molar mass!

14. 16.2
Molarity
Molarity
Calculate the molarity of a solution which contains 0.40 mol of a substance dissolved in 1.6 L of a solution.

15. 16.2
Molarity
Molarity
What is the molarity of a solution containing 325 g of NaCl dissolved in 750. mL of solution?

16. 16.2
Molarity
Molarity
You are making 2.2 L of 3.1 M silver nitrate solution. Who many moles of solute are there?

17. Colligative Properties
16.2
Molarity
Colligative Properties
What is happens when salt is added to water
And……
We try to freeze it?
We try to boil it?