Solution types and_curves
- 1. Factors Affecting Solution Formation Types of Solutions Solubility Curves Unit 8 – Solutions Chapter 15
- 2. Solution Formation Factors that affect solution formation • Temperature – Usually an increase in temperature means and increase in solubility (more solute dissolves) • Except for gases. The increase in temperature means less solubility for a gas. • *A higher temperature means the solute will dissolve faster due to more collisions between solvent and solute molecules
- 3. Increase in Surface Area • Solute that is crushed in smaller pieces will dissolve faster than big chunks. More contact between solute and solvent. Agitation • Mixing of solution will increase number of collisions of solute and solvent molecules. • In general, anything that increases contact between solute and solvent will increase solubility!
- 4. Pressure- (For Dissolved Gases Only) • Increase in pressure will increase the solubility of a gas in a liquid
- 5. Types of Solutions • Unsaturated Solutions – Solutions that can still dissolve more solute. • Saturated Solutions – Solutions that have dissolved as much as they possibly can. Any more solute added would settle at the bottom and not dissolve. • Supersaturated Solutions - Solutions that contain even more dissolved solute than saturated solutions. – Can happen when some solvent evaporates from a saturated solution. It will form crystals when the solution is disturbed.
- 7. SOLUBILITY CURVES • Solubility – The amount of solute required to form a saturated solution with a specific amount of solvent at a specific temperature. • Expressed as grams of solute/100 grams of solvent
- 8. Examples • The solubility of NaCl in water at 80o C is 40grams/100 grams of water • How many grams of NaCl should dissolve in 250 grams of water at 80o C? 250 grams H2O 40 grams NaCl 100 grams H2O = 100 grams NaCl will dissolve
- 9. Things to remember when reading a solubility curve graph • The line of the curve represents a saturated solution for that temperature. • Above this line means you have a supersaturated solution. • Below this line means you have an unsaturated solution.
- 10. 1. If you dissolve 40 grams of KCl in 100 grams of water at 80o C, what type of solution will you have? -Unsaturated 2. If you dissolve 70grams of NH4Cl in 100 grams of water at 50o C, what type of solution will you have? - Super saturated 3. If you dissolve 20 grams of KClO3 in 100 grams of water at 50o C, what type of solution will you have? - Saturated (on the line)