1. I. The Nature of Solutions

2. A. Definitions Solution - homogeneous mixture
Solute - substance being dissolved
Solvent - present in greater amount

3. A. Definitions
Solute - KMnO4
Solvent - H2O

4. B. Solvation First... Then... Solvation – the process of dissolving
solute particles are surrounded by solvent particles
First...
solute particles are separated and pulled into solution
Then...

5. B. Solvation Non- Electrolyte Weak Electrolyte Strong Electrolyte+
sugar - +
acetic acid - +
salt
Non-
Electrolyte
Weak
Electrolyte
Strong
Electrolyte
solute exists as
molecules only
solute exists as
ions and
molecules
solute exists as
ions only
DISSOCIATION
IONIZATION
View animation online.

6. B. Solvation
“Like Dissolves Like”
NONPOLAR
POLAR

7. B. Solvation Soap/Detergent polar “head” with long nonpolar “tail”
dissolves nonpolar grease in polar water

8. C. Solubility UNSATURATED SOLUTION more solute dissolves
no more solute dissolves
SUPERSATURATED SOLUTION
becomes unstable, crystals form
concentration

9. C. Solubility Solubility
maximum grams of solute that will dissolve in 100 g of solvent at a given temperature
varies with temp
based on a saturated soln

10. C. Solubility Solubility Curve
shows the dependence of solubility on temperature

11. C. Solubility Solids are more soluble at... high temperatures.
Gases are more soluble at...
low temperatures &
high pressures (Henry’s Law).
EX: nitrogen narcosis, the “bends,” soda

12. Solutions
II. Concentration

13. A. Concentration The amount of solute in a solution.
Describing Concentration
% by mass - medicated creams
% by volume - rubbing alcohol
ppm, ppb - water contaminants
molarity - used by chemists
molality - used by chemists

14. B. Molality
mass of solvent only
1 kg water = 1 L water

15. C. Dilution
Preparation of a desired solution by adding water to a concentrate.
Moles of solute remain the same.

16. D. Preparing Solutions 1.54m NaCl in 0.500 kg of water
500 mL of 1.54M NaCl
mass 45.0 g of NaCl
add water until total volume is 500 mL
mass 45.0 g of NaCl
add kg of water
500 mL water
45.0 g NaCl
500 mL
mark
volumetric
flask

17. D. Preparing Solutions
Copyright © NT Curriculum Project, UW-Madison
(above: “Filling the volumetric flask”)

18. D. Preparing Solutions
Copyright © NT Curriculum Project, UW-Madison
(above: “Using your hand as a stopper”)

19. D. Preparing Solutions 250 mL of 6.0M HNO3 by dilution
measure 95 mL of 15.8M HNO3
95 mL of 15.8M HNO3
combine with water until total volume is 250 mL
250 mL mark
Safety: “Do as you oughtta, add the acid to the watta!”
water for safety

20. Solution Preparation Lab
Turn in one paper per team.
Complete the following steps:
A) Show the necessary calculations.
B) Write out directions for preparing the solution.
C) Prepare the solution.
For each of the following solutions:
1) mL of 0.50M NaCl
2) 0.25m NaCl in mL of water
3) mL of 3.0M HCl from 12.1M concentrate.

21. III. Colligative Properties
Solutions
III. Colligative Properties

22. A. Definition Colligative Property
property that depends on the concentration of solute particles, not their identity

23. B. Types Freezing Point Depression (tf)
f.p. of a solution is lower than f.p. of the pure solvent
Boiling Point Elevation (tb)
b.p. of a solution is higher than b.p. of the pure solvent

24. Freezing Point Depression
B. Types
Freezing Point Depression
View Flash animation.

25. Boiling Point Elevation
B. Types
Boiling Point Elevation
Solute particles weaken IMF in the solvent.

26. B. Types Applications salting icy roads making ice cream antifreeze
cars (-64°C to 136°C)
fish & insects