1. Entry Task: April 27th Friday
Question:
What is the molarity of 1.2 moles of calcium carbonate in 1.22 liters of water?

2. Agenda: Sign off Discuss Concentration ws Notes on Dilutions
HW: Concentration and Dilution ws

3. 500g water + 75 g ethanol= 575 g solution
1. What is the percent concentration of 75.0 g of ethanol dissolved in g of water?
75.0 g ethanol
= % NaHCO3
500g water + 75 g ethanol
500g water + 75 g ethanol= 575 g solution
75g NaHCO3
X 100
575 g solution
= 13.0% ethanol solution

4. = 33.6% solution 14.2 g benzene = % solution
2. What is the percent concentration of benzene in a solution containing 14.2 grams of benzene in 28.0 grams of carbon tetrachloride?
14.2 g benzene
= % solution
28.0 g CCl g benzene
28.0 g CCl g benzene = 42.2 g solution
14.2g benzene
X 100
42.2 g solution
= 33.6% solution

5. = 54.3g NaOCl Xg NaOCl = 3.62% NaOCl 1500 g solution Xg NaHCO3 = 3.62
3. You have grams of bleach solution. The percent by mass of the solute sodium hypochlorite, NaOCl, is 3.62%. How many grams of NaOCl are in the solution?
Xg NaOCl
= 3.62% NaOCl
1500 g solution
Xg NaHCO3 =
100
1500 g solution
1500 X 3.2 = 5430 g
100
= 54.3g NaOCl

6. = X% by volume ethanol solution
4. What is the percent by volume of ethanol in a solution that contains 35 ml of ethanol in 115 ml of water?
35 ml of ethanol
= X% by volume ethanol solution
35 ml ethanol ml of water
35 ml ethanol
X 100
150 ml solution
= 23.3 %

7. = 25.0 % 25 ml of methanol = X% solution
5. What is the percent by volume of methanol in a solution that contains 25 ml of methanol in 75 ml of water?
25 ml of methanol
= X% solution
25 ml ethanol + 75 ml of water
25 ml ethanol
X 100
100 ml solution
= 25.0 %

8. = 0.148 M 40 g of C6H12O6 1 mole of C6H12O6 180.16 g C6H12O6
6. What is the molarity of an aqueous solution containing 40.0g of glucose (C6H12O6) in 1.5L of solution?
40 g of C6H12O6
1 mole of C6H12O6
g C6H12O6
0.222 moles of C6H12O6
1.5 L solution
= M

9. = 0.128 M 9.5 g of NaOCl 1 mole of NaOCl 74.44 g NaOCl
7. What is the molarity of a bleach solution containing 9.5 g of NaOCl per liter of bleach?
9.5 g of NaOCl
1 mole of NaOCl
74.44 g NaOCl
0.128 moles of NaOCl
1.0 L solution
= M

10. = 0.00814 M 1.55 g of KBr 1 mole of KBr 119.0 g KBr 0.013 moles of KBr
8. Calculate the molarity of 1.60 L of a solution containing 1.55 g of dissolved KBr.
1.55 g of KBr
1 mole of KBr
119.0 g KBr
0.013 moles of KBr
1.60 L solution
= M

11. X moles of Ba(OH)2 = 0.0500 M 0.125 L solution
9. Calculate the number of moles of a 125 ml solution (convert to liters) M Ba(OH)2.
X moles of Ba(OH)2
= M
0.125 L solution
(0.125 L)(0.0500) = moles

12. 89.9 g Ba(OH)2 X moles of Ba(OH)2 = 1.50 M 0.350 L solution
10. Calculate the number of grams of a 350 ml solution (convert to liters) 1.50 M Ba(OH)2.
X moles of Ba(OH)2
= 1.50 M
0.350 L solution
(0.350 L)(1.5) = moles Ba(OH)2
0.525 mol of Ba(OH)2
171.3 g Ba(OH)2
1 mole of Ba(OH)2
89.9 g Ba(OH)2

13. 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) =
MiVi
MfVf =

14. Dilutions: M1V1 = M2V2
Molarity and Volume of the original solution = Molarity and Volume of the diluted solution.
Make sure the volumes match!!!

15. Dilutions: M1V1 = M2V2
P1. What volume, in milliliters of 2.00M calcium chloride (CaCl2) stock solution would you use to make 0.50 L of M calcium chloride solution? Convert liters to milliliters.
(2.00 M)( X)
= (0.300 M )(500 ml)
150
= 75 ml
2.00M

16. Dilutions: M1V1 = M2V2
P2. What volume of a 3.00M KI solution would you use to make L of a 1.25 M KI solution?
(3.00 M)( X)
= (1.25 M )(0.300L)
0.375
= L or 125 ml
3.00M

17. Dilutions: M1V1 = M2V2
P3. If I add 25 ml of water to 125 ml of a 0.15 M NaOH solution, what will the molarity of the diluted solution be?
(0.15 M)( 125 ml)
= (X M )(150 ml)
18.75
= M
150 ml

18. Use the rest of the period to work on homework