1. Solubility

2. 2 Parts to All Solutions sugar solution
Solvent – The part of the mixture present in the greatest amount (part doing the dissolving).
greatest amount
Solute – The part or parts of the mixture present in the lesser amount (part being dissolved).
lesser amount
Ask students which is solute/solvent in each.
sugar-solute
sugar-solute
water-solvent
water-solvent
sugar solution

3. What is solubility?
the amount of solute that will dissolve in a given amount of solvent at a specific temperature and pressure

4. What is dissolving?
Dissolving happens when the solvent, usually water molecules, collide with the solute and pull it apart piece by piece.

5. 3 types of solutions (based on the amount of solute)
saturated – a solution is holding the maximum amount of solute possible, and more solute added would collect at the bottom.
unsaturated – more solute can be added and will still dissolve.
super saturated – more solute than should be possible at that temperature and pressure is dissolved (Ex: ‘Sweet’ tea)

6. How can we change the amount that will dissolve?
The solubility of a substance (the amount that will dissolve) depends on three factors:
Temperature
Pressure
Type of substance
To increase the amount of solid that will dissolve in a liquid you would need to
- Increase the temperature
- Decrease the pressure

7. Can we make something dissolve faster?
Stirring/shaking: brings more fresh solvent in contact with more solute.
Crushing/grinding: increases the surface area.
Increasing the temperature: speeds up the movement of the solvent particles creating more collisions with the solute.

8. Can we make something dissolve faster?
Stirring/shaking: brings more fresh solvent in contact with more solute.
Crushing/grinding: increases the surface area.
sugar-solute
water-solvent
sugar solution
Increasing the temperature: speeds up the movement of the solvent particles creating more collisions with the solute.

9. In the real world!
Timed release capsules control how fast medicine dissolves.
When making tea (even iced tea) you have to steep the tea bag in boiling hot water.

10. Can a gas dissolve in a liquid?
Gas solutes are all around you!
CO2 in coke
Dissolved O2 in lakes, rivers, oceans
Fish have gills which absorb oxygen from the water…humans obviously do not!

11. How can a gas dissolve in a liquid?
The solubility of a gas also depends on temperature and pressure.
As temperature decreases, more gas will dissolve.
As pressure increases, more gas will dissolve.