Solutions
DAY 1&2
Matter- substances vs mixtures
Demo #1: Making a solution
solvent: (yellow/blue/green) colored liquid which
was the part that _________
solute: (yellow/blue/green) colored liquid which
was the part that______________
solution: (yellow/blue/green) colored liquid which
was the part that _____________
Solvation: making a solution
 Video Clip #1
 Video Clip #2
 PhET
How does solvation happen between salt and water?
Lets make a solution continued
When watching the clip, make sure you can explain
why the rate of dissolving is affected by:
1. Hot versus cold water
2. Size of solute (particle size)
3. Stirring versus not stirring
Video Clip
Factors that affect solution formation
Ways to increase the opportunities of solute
1. Higher temperature
a.
b.
faster moving solvent particles = more collisions
solute breaks free faster
2. Agitation (stirring)
a.
b.
c.
faster moving particles= more collisions
Solute breaks free faster
Sweeping away the dissolved portion
3. Smaller Particle Size
a.
more total surface area = more possible collision sites
Likes Dissolve Likes
1. Have you ever used Italian dressing or any kind of vinaigrette?
Why do you have to shake the bottle before you using it? Why
does this happen?
2. Have you ever washed your hands after getting oil on them? What
happens if you just rinse them with water? Why is this?
Demo #2: Likes dissolve Likes
Blue colored isopropyl alcohol (C3H7OH), Red colored water (
H2O), & Yellow Vegetable oil (C6H5O6) are mixed together.
Now, answer the following:
1. What happened when all three were added
together?
2. Explain why these observations make sense.
3. What did the color change represent?
4. Why is water considered to a universal solvent?
5. Compare the terms Soluble and Insoluble.
Likes Dissolve Likes
Conclusion to demo:
Water is polar or nonpolar
Isopropyl alcohol is polar or nonpolar
Vegetable oil is polar or nonpolar
Likes Dissolve Likes
Water:
Carbon Tetrachloride:
Likes Dissolve Likes
Solutes
Molecular Shape if applicable
Polar, Ionic, or
Nonpolar
Solvents
Water
Carbon
Tetrachloride
Potassium
Nitrate
Soluble or
Insoluble
Soluble or
Insoluble
Iodine
Soluble or
Insoluble
Soluble or
Insoluble
Boron
Trifluoride
Soluble or
Insoluble
Soluble or
Insoluble
Nitrogen
Trichloride
Soluble or
Insoluble
Soluble or
Insoluble
Look at the image below, what word would you use
to describe: miscible or immiscible.
Look at the image below, what word would you use
to describe: miscible or immiscible.
Demo # 3
Determine if the following are strong, weak, or
nonelectrolytes. Explain why the observations
make sense.
1.
2.
3.
4.
5.
6.
Solid NaCl
NaCl (aq)
C12H22O11
1M HCl (strong acid)
6M HCl (strong acid)
HC2H3O2 (weak acid)
Electrolyte vs Nonelectrolyte
 Electrolytes: conduct electricity
 Ionic substances and strong acids
 The higher the concentration the stronger the
electrolyte. Why do you think this is?
Chemistry Music Video
SOLUTION SONG
Molarity
Formula:
moles of solute
Liter of solution
*** remember if your solute is
given/measured in grams you can convert
to moles by using molar mass ( unit 5)
Molarity
Unit(s) : moles/L or molar or
M (which stands for molar) or [value in brackets]
ex: 3 moles/L or 3 molar or 3M or [3]
Molarity
Vocab;
Concentrated: a lot of solute per solvent
Dilute: small amount of solute per solvent
Think of the following scenario:
Your making chicken & stars soup, you dump the
can into a bowl (this is concentrated) and then
you add water (making it more dilute).
Examples
1.
A saline solution contains 0.90 g NaCl in exactly 100mL of
solution. What is the molarity of the solution?
2. How many moles of solute are present in 1.5L of 0.24M
Na2SO4?
Molarity by Dilution
Purpose: making a more dilute solution
Formula:
M1V1 = M2V2
How many milliliters of a stock solution of 2.00M MgSO4
would you need to prepare 100.0 mL of 0.400M MgSO4?
Chemistry Music Video
FOR THOSE ABOUT TO DISSOLVE WE SOLUTE
YOU
Colligative Properties
Why do we salt the roads in the winter? How does
it work?
2. Why would you add salt to a pot of water before it
boils?
3. Why do you add antifreeze to your car in the
winter? How does it work?
4. Why do you add coolant to your car in the
summer? How does it work?
1.
Colligative Properties
When a solute is added to a solvent, it can change
some solvent properties like:
- raising the boiling point
- lowering the freezing point
Colligative Properties: vapor pressure
When adding a solute to a solvent, it
(decrease/increases) the vapor pressure of the liquid.
Colligative Properties: freezing point
Book Clip
When adding a solute to a solvent, it is harder
for the solvent to form a _______ network. So
more energy needs to be removed resulting in
a (lower/higher) temperature at which it
becomes a solid (freezing point). The more
solute added the (lower/higher) the freezing
temperature.
Colligative Properties: boiling point
Book Clip
Boiling is when the _____pressure =
atmospheric pressure. When a solute is
added (more/less) energy needs to be added
to cause the vapor pressure to equalize with
the atmospheric pressure. Therefore the
temperature at which a solution boils is
(higher/lower) than the pure solvent.