1. BELL WORK
What is a chemical solution? Try to explain it as if to a 5th grader, be as “scientific” as possible!
To play the movies and simulations included, view the presentation in Slide Show Mode.

2. Homework Packet Turn-In
Pressure Conversions-ppt. 1-6
White review—Boyles’ 1-4
White review Charles’ 5-8
White review Combined 9-13
White Review Mixed 14-20
Ideal and Combined (white sheet) 1-19 odds.
Gas Stoichiometry (white sheet) 1-4, 5-10.

3. 10 March 2014
Objective: You will KNOW the parts of a solution, UNDERSTAND how to calculate molarity, and tommorow APPLY your knowledge to making solutions
Agenda:
Solutions
Solubility
Molarity

4. Concentration and Reaction Rates Video

5. Some Definitions
A solution is formed when a ____________ and _____________are mixed.
Solvent
Solute

6. PARTS OF SOLUTIONS
SOLUTE –what’s being dissolved (usually the lesser amount)
SOLVENT –what’s dissolving the solute (usually the greater amount)
Solute + Solvent = Solution

7. Definitions Solutions can be saturated or unsaturated.
__________solution contain the maximum amount of solute.
An __________solution contains less solute than a solvent can hold at a particular temp.
Saturated
unsaturated

8. Definitions
SUPERSATURATED SOLUTIONS contain more solute than a solvent can hold
They are unstable. The super saturation is only temporary, and usually accomplished in one of two ways:

9. To Make a Supersaturated Solution
Warm the solvent so that it will dissolve more, then cool the solution
Evaporate some of the solvent carefully so that the solute does not solidify and come out of solution.

10. Supersaturated Rock Candy
This supersaturated sucrose and food coloring solution uses a “seed” crystal to make…
Crystal Rock candy

11. Factors affecting solubility—dissolve
Heat
1. _______ increases solubility in most liquids
* solubility of_________ are greater in cold water than hot.
2. ________ the solubility of gas increases w/ increasing pressure
gases
True:

12. Polarity Review

13. Factors affecting solubility
Polar
3. __________ molecules will only dissolve in _________ molecules
Non- polar molecules will only dissolve in non-polar molecules
“_________dissolves__________”
Polar
like
like

14. Polarity Recall
"polar" molecules: An uneven distribution of electron density. Ex. water H2O
“non polar” molecules: an even distribution of electron density.
Ex. Oil, propane, etc.

15. Question
A solution is made up of 25 grams of cyclohexane (non-polar) and 7 grams of acetonitrile (polar).
What is the solute ?
What is the solvent?
Would you expect the solvent to readily mix with the solute?

16. With your neighbor
Mr. Brunenkant tried to mix butanol (non-polar) with cyclohexane (non-polar) to make a solvent that would clean a water soluble crystal residue on his desk.
1. Will the two solvents mix readily?
2. Do you think the solvent mixture would dissolve the water soluble crystals? Why or why not?

17. Concentration of a solution
The amount of solute in a solution is given by its concentration.
M = mol L
Molarity ( M ) =
moles solute
liters of solution

18. Less than 1.0 L of water was used to make 1.0 L of solution. Why?

19. Practice
Dissolve 5.00 g of NiCl2 in enough water to make 250 mL of solution. Calculate the Molarity.

20. Step 1: Calc. moles of NiCl2
Dissolve 5.00 g of NiCl2 in enough water to make 250 mL of solution. Calculate the Molarity.
Step 1: Calc. moles of NiCl2
Step 2: Calculate Molarity
[NiCl2] = M

21. What amount (grams) of NiCl2 is needed to make a 0
What amount (grams) of NiCl2 is needed to make a 0.1M solution at a volume of 100ml?
Step 1: Calc. moles of NiCl2in 100ml 0.1M sol.
0.01moles
0.100L x 0.1mol/L =
Step 2: Calculate grams
0.01mol x 129g/mol =
1.29grams

22. What amount (grams) of NaCl is needed to make a 0
What amount (grams) of NaCl is needed to make a 0.5M solution at a volume of 500ml?
Step 1: Calc. moles of NaCl in 500ml 0.5M sol.
0.25moles
0.500L x 0.5mol/L =
Step 2: Calculate grams
0.25mol x 58g/mol =
14.5grams

23. Closure Write down your answer: What is a chemical solution?
What is a solute?
What is a solvent?

24. Homework What is the molarity of 7 g of NaCl in 300 mL of water?
What is the molarity of 12 g of KBr in 700 mL of water?
If you have a 0.7 molar NaCl solution, how many moles of NaCl are there in 1200 mL?
Based on your answer from #3, how many grams would that be?

25. BW 3-12-13 What is the molarity if you have 3.7 moles and 2.1 L?
If you dissolve g of CaCl2 in enough water to make 500 mL of solution, what is the Molarity?

26. 12 March 2013
Objective: You will understand molarity and how to calculate it.
Agenda:
Molarity
Practice

27. moles = M•V Using Molarity
What mass of oxalic acid, H2C2O4, is required to make 250. mL of a M solution?
moles = M•V

28. moles = M•V Using Molarity
What mass of oxalic acid, H2C2O4, is required to make 250. mL of a 0.05 M solution?
moles = M•V
Step 1: mL  L.
250 mL x 1L/1000mL = L
Step 2: Calculate.
Mol=(0.05 mol/L) (0.250 L) = mol
Step 3: Convert moles  grams.
( mol)(90.00 g/mol) = g

29. Practice
How many grams of NaOH are required to prepare 400 mL of 3.0M NaOH solution?
1) 12 g
2) 48 g
3) 300 g

30. Practice makes Perfect
Calculate the molarity when 75.0 grams of MgCl2 is dissolved in mL of solution.
100.0 grams of sucrose (C12H22O11)is dissolved in 1.50 L of solution. What is the molarity?

31. Molarity Pre-lab time!
Get a sheet of paper out and title it:
Determining Molarity Lab

32. HW: Problems 1-11 odds

33. BELL WORK
What is the molarity of a solution with 6.2 grams of HNO4 dissolved in 350ml of water?
If molarity of HNO4 is .090 M and you have 5 liters, how many moles is that? Grams?

34. Happy Pi Day! BELL WORK 3-14-13
49.8 grams of KI is dissolved in enough water to make 3.14 L of solution. What is the molarity?
What makes up a solution?
How do you increase solubility?
What type of substance does a polar substance dissolve in?

35. Bell Work 3/15/2013
What is the molarity of a solution if it has 7 moles of HCl and there are 2.1 L of solution?
How many grams of KBr must you weigh out in order to make 500 mL of a 3M solution?

36. 15 March 2013
Objective: you will understand how to use the dilutions formula and apply it in a laboratory setting
Agenda:
Dilutions
“Killer Kool Aid Lab”--Friday

37. M1V1=M2V2 DILUTION Going from one concentration to another
M = molarity (mol/L)
V = volume (what unit ????)
Starting/ what you have M1 and V1
Ending/ what you want M2 and V2

38. 4.5

39. Dilution is the procedure for preparing a less concentrated solution from a more concentrated solution.
Dilution
Add Solvent
Moles of solute
before dilution (i)
after dilution (f) =
M1V1
M2V2 =
4.5

40. How would you prepare 60.0 mL of 0.2M HNO3 from a stock solution of 4.00 M HNO3?
M1V1 = M2V2
M1 = 4.00
M2 = 0.200
V2 = 0.06 L
V1 = ? L =
0.200 x 0.06
4.00
V1 =
M2V2 M1
= L = 3 mL
+ 57 mL of water
3 mL of acid
= 60 mL of solution

41. DILUTION
What would the new molarity be of a 250ml 0.8M solution of HCl if it was diluted to 450ml?

42. Practice
What is the molarity of a solution with 2.0 grams of NaOH dissolved in 300ml of water. What would be the new molarity if you diluted to solution of 630ml?

43. Bellwork
How many moles of KNO3 are needed to create 500 mL of 6.0M solution of KNO3?

44. Lab Time
Killer Kool Aid!!!

45. mL of killer Kool aid needed
Lab Time
Killer Kool Aid!!!
Molarity
Red Blue Green
2.20M M M
mL of killer Kool aid needed
Observations 1
0.176
0.135
0.324 2
0.110
0.105
0.216 3
0.088
0.075
0.180 4
0.066
0.045
0.144 5
0.44
0.30
0.72
So, group 1 does dilutions for Red 2.2M 0.176, Blue 1.50M 0.135M, Green 3.60M  0.324M.

46. Preparing Solutions
Weigh out a solid solute and dissolve in a given quantity of solvent.
Dilute a concentrated solution to give one that is less concentrated.

47. Equivalence point the point at which the reaction is complete
Titrations
In a titration a solution of accurately known concentration is added gradually added to another solution of unknown concentration until the chemical reaction between the two solutions is complete.
Equivalence point the point at which the reaction is complete
Indicator – substance that changes color at (or near) the
equivalence point
Slowly add base
to unknown acid
UNTIL
the indicator
changes color

48. Acid Base Rxn Titration
H2C2O4 (aq) + 2NaOH (aq) Na2C2O4 (aq) + 2H2O (l)
acid base
Carry out this reaction using a TITRATION.
Oxalic acid,
H2C2O4

49. Setup for titrating an acid w/ a base

50. Titration 1. Add solution from the buret.
2. Reagent (base) reacts with compound (acid) in solution in the flask.
Indicator shows when exact stoichiometric reaction has occurred. (Acid = Base)
This is called NEUTRALIZATION.

51. For most Acid-Base Rxns
The generic equation for most acid base rxn is:
AH + BOH  AB + H2O
You will get a salt and water out of an acid base rxn!

52. You try… write out the products:
AH + BOH  AB + H2O
You will get a salt and water out of an acid base rxn!
1) HCl + NaOH 
2) HNO3 + KOH 
3)TrickyCH3COOH + NaOH 
NaCl +
H2O
KNO3 + H2O
NaCH3COO + H2O
Acetate ion

53. WRITE THE BALANCED CHEMICAL EQUATION!
What volume of a M NaOH solution is required to titrate mL of a 4.50 M H2SO4 solution?
WRITE THE BALANCED CHEMICAL EQUATION!
H2SO4 + 2NaOH H2O + Na2SO4 M
acid
Mole
Bridge
volume acid
moles acid
moles base
volume base M
base
4.50 mol H2SO4
1000 mL soln x
2 mol NaOH
1 mol H2SO4 x
25.00 mL
1000 ml soln
1.420 mol NaOH x
= 158 mL