1. Solutions Solutions * ‘homogeneous mixtures’
Particles are evenly or uniformly distributed throughout the sample
2 or more components physically combined in varying amounts
(gaseous, liquid, or solid solution)

2. NaCl is the solute, Water is the solvent
Solutions
*one substance dissolved in another
* Solute – substance dissolved
(smaller amt)
* Solvent – substance doing the dissolving
(larger amt)
Example: NaCl(aq)
NaCl is the solute, Water is the solvent

3. Solutions
*Solute & solvent are NOT chemically combined, therefore they can be physically separated.
If you heat a NaCl solution, the water will evaporate and you will be left with solid NaCl in the beaker.
Filtration does NOT separate a solute from a solvent!!

4. Solutions Each substance retains its own properties
In an NaCl solution, the NaCl is still salty and the water is still wet!

5. Solutions Clear or transparent (if aqueous)
Particles do NOT settle on standing
You can see through it.

6. The Solution Process

7. Water is a Polar Molecule

8. NaCl(aq)  NaCl(s)  Na+(aq) + Cl-(aq)

9. NaCl dissolved in water

10. Factors Affecting the Dissolving Rate
Temperature
Solids dissolve better at high temps
Gases dissolve better at lower temps
Agitation
Stirring or shaking helps
Surface Area
When you powder a solid, you increase the exposed surface and it dissolves faster

11. Factors Affecting the Dissolving Rate
Pressure
If you increase the pressure on the surface of a liquid, more gas will dissolve in it.
Increase pressure = Increased solubility of a GAS

12. What causes the hissing sound?
Soda Pop
What causes the hissing sound?
When you open the cap, the pressure decreases and the gas becomes less soluble in the soda, so the carbon dioxide gas comes rushing out.

13. Factors Affecting the Dissolving Rate
Nature of the chemical

14. Vocabulary Universal Solvent = Water
Aqueous Solution (aq) = dissolved in water
Soluble vs Insolube
dissolves doesn’t dissolve
Miscible vs Immiscible
2 liquids mix liquids separate
(soluble) (insoluble)

15. Like Dissolves Like