1. Ch. 15 Solutions
Water is a ___________ molecule and therefore __________.
Water forms _______________ ________ which strongly bonds the molecules together with each other. These intermolecular bonds give water some very unique properties:
1) High surface tension: acts like a thin “________” on the surface.
_______________ are used to reduce water’s surface tension so it can “wet down” a surface such as clothing.
bent
polar
hydrogen
bonds
skin
Detergents
“Water Strider”

2. Surface Tension of Water
metal paper clip on water
water forms “beads”

3. More Unique Properties of Water
2) Low vapor pressure and high ___________ _______ : needs a lot of energy/heat to make it evaporate or __________.
3) High specific heat: takes a lot of heat to change its _____________.
boiling point
boil
temperature
The cheese of a pizza has a lower specific heat than water so it cools down __________.
The pizza sauce has a high moisture content, so it has a specific heat similar to water. It stays hot much ____________.
Therefore, you will burn your mouth on the sauce if you are not careful!
faster
longer

4. Specific Heat and “Sea Breezes”
The land has a ___________ specific heat than water.
As the land heats up ____________ than the water, it creates a difference in _____________.
This makes a breeze form that flows from the water to the land.
low
quicker
pressures
In Chicago, this “sea breeze” from the lake to the shore keeps the temperature at the lakefront ___________ during the heat of the day.
The breeze reverses direction at night as the land cools off _________ than the water, and the temperature is therefore ___________ at the lakefront at night.
cooler
faster
warmer

5. More Unique Properties of Water
4) Water makes 6-sided (hexagonal) ___________ of ice or snow.
crystals
5) Water readily dissolves other _____________ substances and ionic solids/salts.
polar

6. Aqueous Solutions There are two parts to a solution:
1) ____________- the dissolving medium which is typically a liquid or the substance in greater amount when 2 similar phases are mixed
2) _____________ - the substance that dissolves
Solvent
Solute

7. Examples of common solutions:
Kool-aid = _________ in _______
Air = ____ in ____
sugar
water O2 N2
14K gold = _______ in _________
silver
gold

9. Examples of common solutions:
__________ = copper in zinc
Cola Drinks = sugar in water and ______ in ___________
Brass
CO2
water

10. “Like Dissolves Like”
This phrase means that polar solvents dissolve __________ solutes and nonpolar solvents dissolve ___________ solutes.
Example: Mix together water, oil, table salt, and iodine (I2).
What dissolves in what? ________________
____________________________________
polar
nonpolar
The nonpolar oil will dissolve the nonpolar I2
and the water dissolves the salt since they are
both polar.

11. nonpolar grease remover
“Like Dissolves Like”
nonpolar grease remover

12. Vinegar & oil dressing will separate. Shake well before using!
“Like Dissolves Like”
Vinegar & oil dressing will separate. Shake well before using!

13. Solubility tells us how much _________ can dissolve in a certain amount of _____________ at a particular temperature and pressure to make a “__________________” solution.
Solution Vocabulary
_________________ solutions: the solution cannot hold any more solute. (Some solute may be sitting on the bottom of the container.)
________________ solutions: the solution could dissolve more solute
____________________ solutions: the solution is holding more than it should at the given temperature, and if you messed with the solution by shaking it or throwing in one more crystal, the whole thing would _________________ rapidly!
solute
solvent
saturated
Saturated
Unsaturated
Supersaturated
crystallize

15. Supersaturated Sodium Acetate Solution
Steve Spangler Science Video

16. Solution Vocabulary
_______________ : two liquids that can dissolve in each other
Example: ____________ in water
_________________ : the liquids don’t mix
Example: _____ and water
Miscible
alcohol
Immiscible
Oil

17. Factors that Affect Solubility
1) Temperature:
a) Gas dissolved in Liquid: As temperature_____ , solubility ______.
Examples: O2 in a fish tank…(________ water suffocates fish.)
CO2 in soda… (_________ soda loses fizz.)
inc.
dec.
Warm
Warm

18. Factors that Affect Solubility
Tested Dissolved Oxygen, Conductivity,
Salinity (salt concentration), and Temperature.

19. Factors that Affect Solubility
Tested Dissolved Oxygen, Conductivity,
Salinity (salt concentration), and Temperature.

20. Factors that Affect Solubility
Tested Dissolved Oxygen, Conductivity,
Salinity (salt concentration), and Temperature.

23. Factors that Affect Solubility: Temperature
b) Solid dissolved in Liquid: As temperature ______ , solubility “generally” ________________.
Example: sugar in hot tea vs. sugar in iced tea
inc.
increases

24. Factors that Affect Solubility: Temperature
(abnormal behavior)

25. Factors that Affect Solubility
2) Pressure:
a) Gas dissolved in Liquid: As pressure _____ , solubility ______.
Examples: CO2 in soda: (made under _______ pressure)
inc.
inc.
high

26. Factors that Affect Solubility: Pressure
Examples (continued): O2 in your blood stream while scuba diving: “____ _________”. This can cause _________ to form in your blood stream which can lead to ________ pain, ___________ and _______ __________.
the bends
bubbles
joint
strokes
heart attacks

27. “The Bends” a) Surfacing too fast b) Surfacing and decompressing a) b)
c) O2 can become toxic at too high of a concentration in your body!! c)

29. Decompression Chamber

30. Factors that Affect Solubility: Pressure
b) Solid dissolved in Liquid: As pressure ___________ , solubility ______ ______ _____________!!
Since you cannot compress either a solid or a liquid, pressure has ____ effect on the solubility!
Question: What are 3 things you can do to get a solid to dissolve more rapidly in a liquid? 1) 2) 3)
inc.
does not change no
Heat up the solution.
Stir the solution.
Crush the solid.

31. Measuring the Concentration of a Solution
___________________: how much solute is dissolved in a certain amount of solvent at some given temperature and pressure.
Qualitative Vocabulary
_______________ : contains a small amount of solute
_______________ : contains a large amount of solute
Concentration
Dilute
Concentrated
concentrated
dilute

32. concentrated
dilute

33. Calibration Curves
A standard solution is a solution of__________________. These solutions can be used to predict properties of an unknown solution.
At least _________ data points are used and then plotted with a line of best fit.
known concentration
three
Beer’s Law

34. Calibration Curves
If spectrometer reads the absorbance at 0.48 what is the molarity?
What would you predict the absorbance of a 7M solution to be?
3.12 M
0.62

36. Quantitative Vocabulary:
____________: moles of solute per liter of solution
_______________ ( ) = moles of solute ÷ Liters of solution
Practice Problem: What is the molar concentration of an aqueous NaCl solution when 25.0 grams are dissolved in water to make 500 mL of solution?
Molarity
Molarity M
moles
Grams of solute = (M) x (L) x (Molar Mass)
Molarity X
Liters
25.0 g = (M) x (0.500 L) x (58.5 g/mole)
Molarity = M

37. Making a Solution of a Required Concentration
# of moles
÷ # of liters
= Molarity

39. “Add acid to water, do as you ought-er.”
Making Dilutions
Dilution: Making a solution _______ concentrated by ________ more ___________ .
Important: When diluting acids:
“Add acid to water, do as you ought-er.”
M1xV1=M2xV2
M1 -- the initial concentration of the solution.
V1 -- the initial volume of the original solution that is going to be diluted with water.
M2 -- the final concentration of the solution after it’s diluted with water.
V2 -- the total volume of the final solution after it has been diluted with water.
less
adding
solvent

40. Making Dilutions M1xV1=M2xV2 Practice Problems:
1) The science department buys HCl in large bottles that have a concentration of 12 Molar. The science teacher then dilutes the acid for labs. How would the teacher make 2.0 liters of a 2.5 M HCl solution from this “stock” solution?
2) What is the final concentration of a sugar solution if 300 mL of water is added to 500 mL of a 2.5 M sugar solution?
( ) ( ) = ( ) ( )
12 M V1
2.5 M
2.0 L
V1 = L
Take L of the stock solution and add it to some water and then add enough water to make a final volume of 2.0 liters.
( ) ( ) = ( ) ( )
2.5 M
500 mL M2
800 mL
M2 = 1.56 M

41. Freezing Points and Boiling Points of Solutions
Any solute added to a liquid will _____________ the freezing point of the liquid.
In other words, if you put salt into water, instead of it freezing a 0˚C, it will freeze somewhere _________ zero depending on how concentrated the solution is.
Uses include making homemade ice cream and melting ice on a sidewalk.
lower
below

42. Freezing Point Depression

43. Freezing Points and Boiling Points of Solutions
Any solute added to a liquid will _____________ the boiling point of the liquid. In other words, if you put salt into water, instead of it boiling a 100˚C, it will boil somewhere ________ 100˚C depending on how concentrated the solution is. The solute decreases the solution’s vapor pressure. (See Fig )
Since ionic solids break up into multiple ions when dissolving, they actually change the F.P. & B.P. __________ than a molecule would.
That’s one reason why we use salts to melt ice instead of using sugar.
raise
above
more
lowest freezing point & highest boiling point

44. Boiling Point Elevation
Boiling Point (sea level):
219° F at 40 percent concentration 222° F at 50 percent 225° F at 60 percent

45. Freezing Points and Boiling Points of Solutions
Solvent boiling point
Solution boiling point