MR. SURRETTE
VAN NUYS HIGH SCHOOL
CHAPTER 10: CHEMICAL SOLUTIONS
WORKSHEET SOLUTIONS
1. Chemical solutions are __________ mixtures of solute and solvent.
1A. homogenous
2. Two or more substances homogenously combined together is a:
2A. solution
3. Gas solutions consist of __________ dissolved in __________ .
3A. gases gases
4. The __________ is the substance least present in a solution.
4A. solute
5. Methanol dissolves best in __________ solutions.
5A. polar
6. The __________ is the substance most present in a solution.
6A. solvent
7. Rock candy is a good example of a __________ solution.
7A. supersaturated
8. Carbon dioxide in soda is an example of a __________ solution.
8A. liquid-gas
9. __________ solutions have a high solute percentage.
9A. Concentrated
10. Solutes __________ by separating into ions or molecules.
10A. dissolve
11. The solubility of most solutions is greatly affected by:
11A. temperature
12. Calculate the % mass of 14.7 grams sucrose dissolved in 412.1 mL water.
12A.
(1) 412.1 mL water = 412.1 g water
(2) mass of solvent = 412.1 g
(3) mass of solute = 14.7 g
(4) mass of solution = mass of solute + mass of solvent
(5) mass of solution = 14.7 g + 412.1 g
(6) mass of solution = 426.8 grams
(7) % mass = (mass solute / mass solution) x 100
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CHEMISTRY
MR. SURRETTE
VAN NUYS HIGH SCHOOL
12A. (continued...)
(8) % mass = (14.7 g / 426.8 g) x 100
(9) % mass = 3.44%
13. Soda is 9.5% sucrose. What volume of soda in mL contains 72.7 g sucrose? (Assume the density
of soda = (WATER).
13A.
(1) 9.5 % sucrose = (9.5 g sucrose / 100 mL)
(2)
72.7 g sucrose
(100 mL soda)
V = ------------------- x ------------------1
(9.5 g sucrose)
(3) Volume = 765.3 mL
14. Soda is 9.5% sucrose. How many grams of sucrose are found in 355 mL of soda?
14A.
(1) 9.5% sucrose = (9.5 g sucrose / 100 mL soda)
(2)
355 mL
(9.5 g sucrose)
Mass = ----------- x ------------------1
(100 mL)
(3) Mass = 33.7 g
15. What is the molarity of a solution that contains 5.5 grams NaCl dissolved in 1.2 liters water?
15A.
(1) Na = 22.99 amu
(2) Cl = 35.45 amu
(3) NaCl = 58.44 g/mol
Convert grams NaCl to moles:
(4)
5.5 g
(1 mol NaCl)
NaCl = ------------ x ----------------- = 9.41 x10-2 mol
1
(58.44 g)
Compute molarity of solution:
(5)
(9.41 x10-2 mol)
M = -------------------- = 7.84 x 10-2
(1.2 L)
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CHEMISTRY
MR. SURRETTE
VAN NUYS HIGH SCHOOL
16. How many liters of 0.724 M NaOH solution contain 1.24 moles NaOH?
16A.
(1) 0.724 M NaOH = (0.724 mol NaOH / 1 liter)
(2)
1.24 mol NaOH
(1 liter)
Volume = -------------------- x ---------------1
(0.724 mol)
(3) Volume = 1.71 L
17. How much 4.0 M NaNO3 is needed to make 0.585 L of 1.2 M NaNO3 solution?
17A.
Given: MI = 4.0 M, MF = 1.2 M, VF = 0.585 L
Find: VI
(1) MIVI = MFVF
(2) VI = MFVF / MI
(3) VI = (1.2 M)(0.585 L) / (4.0 M)
(4) VI = 1.76 x 10-1 L
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CHEMISTRY
MR. SURRETTE
VAN NUYS HIGH SCHOOL
CHAPTER 10: CHEMICAL SOLUTIONS
QUIZ SOLUTIONS
1. More solute can dissolve in __________ solutions.
1A. unsaturated
2. Two grams of sugar are added to a sugar water solution and stirred thoroughly. Twenty grams of
sugar then form on the bottom of the container. This solution is:
2A. supersaturated
3. Cations and anions in liquid solutions are:
3A. electrolytes
4. By definition, all solutions are:
4A. homogenous
5. Ethyl alcohol dissolves best in __________ solutions.
5A. non-polar
6. Solutes __________ by separating into ions or molecules.
6A. dissolve
7. __________ solutions have a high solute percentage.
7A. Concentrated
8. __________ solutions have a low solute percentage.
8A. Dilute
9. The density of water is:
9A. 1.0 g/ mL
10. Liquid solutions consist of __________ dissolved in liquids.
(A) liquids (B) gases (C) solids (D) all of these (E) none of these
11. Pure oxygen in water is an example of a __________ solution.
11A. liquid-gas
12. Unstable solutions that precipitate to the saturation level are:
12A. supersaturated
13. The __________ is the substance most present in a solution.
13A. solvent
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CHEMISTRY
MR. SURRETTE
VAN NUYS HIGH SCHOOL
Questions 14 – 15. An ingot is formed by mixing 102 grams of copper with 112 grams
of zinc.
14. What is the percentage of copper based on relative mass?
14A.
(1) Mass solution = solute + solvent
(2) Mass solution = 102 g + 112 g
(3) Mass solution = 214 g
For copper:
(4) Mass copper / mass solution
(5) 102 g / 214 g
(6) 0.477 x 100%
(7) Cu = 47.7%
15. Re-compute the copper concentration within the ingot using mole fractions.
15A.
Moles of zinc:
(1) 112 g Zn 1 mole
------------ = 1.71 mole Zn
65.39 g
Moles of copper:
(2) 102 g Cu 1 mole
----------- = 1.61 mole Cu
63.55 g
Total moles:
(3) Total moles = Zn moles + Cu moles
(4) Total moles = 1.71 moles + 1.61 moles
(5) Total moles = 3.32 moles
Mole fraction:
(6) Cu mole fraction = 1.61 moles / 3.32 moles
(7) Cu mole fraction = 0.485 x 100%
(8) Cu = 48.5%
16. 231 grams of acetic acid is added to 512 grams of water. What is the molality of acetic acid in the
solution?
16A.
Molecular weight of acetic acid:
(1) 2 x C = 2(12.01 amu) = 24.02 g C
(2) 4 x H = 4(1.01 amu) =
4.04 g H
(3) 2 x O = 2(16.00 amu) = 32.00 g O
=========
CH3COOH molecular weight = 60.06 grams
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CHEMISTRY
MR. SURRETTE
16A. (continued…)
Moles of acetic acid:
(4) 231 g CH3COOH
VAN NUYS HIGH SCHOOL
1 mol
----------- = 3.85 mol CH3COOH
60.06 g
Molality of acetic acid:
(5) 3.85 mol CH3COOH / 0.512 kg water
(6) m = 7.51
17. Calculate the relative mass of 19.2 grams potassium fluoride dissolved in 412.1 mL water.
17A.
(1) 412.1 mL water = 412.1 g water
(2) mass of solvent = 412.1 g
(3) mass of solute = 19.2 g
(4) mass of solution = mass of solute + mass of solvent
(5) mass of solution = 19.2 g + 412.1 g
(6) mass of solution = 431.3 grams
(7) % mass = (mass solute / mass solution) x 100
(8) % mass = (19.2 g / 431.3 g) x 100
(9) % mass = 4.5%
Questions 18 - 19. A solution is 7.5% ethyl alcohol. What volume of solution in mL contains 185.2 g
ethyl alcohol? (Assume the density of ethyl alcohol = (WATER).
18A.
(1) 7.5 % ethyl alcohol = (7.5 g ethyl alcohol / 100 mL water)
(2)
185.2 g ethyl alcohol
(100 mL water)
Volume = -------------------------- x -----------------------1
(7.5 g ethyl alcohol)
(3) Volume = 2469 mL
19. How many grams of ethyl alcohol are found in 355 mL of solution?
19A.
(1) 7.5% ethyl alcohol = (7.5 g ethyl alcohol / 100 mL water)
(2)
355 mL
(7.5 g ethyl alcohol)
Mass = ---------- x --------------------------1
(100 mL water)
(3) Mass = 26.6 g
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CHEMISTRY
MR. SURRETTE
VAN NUYS HIGH SCHOOL
20. What is the molarity of a solution that contains 27.2 grams KNO3 dissolved in 0.9
liters water?
20A.
(1) KNO3 Molecular Weight:
1 x K = 1 x 39.10 amu = 39.10 g
1 x N = 1 x 14.01 amu = 14.01 g
3 x O = 3 x 16.00 amu = 48.00 g
======
KNO3 = 101.11 g/mol
Convert grams KNO3 to moles:
(2) KNO3 = 27.2 g (1 mol KNO3 / 101.11 g)
(3) NaCl = 2.69 x 10-1 mol
Compute molarity of solution:
(4) M = (2.69 x 10-1 mol NaCl / 0.9 L)
(5) M = 2.99 x 10-1
21. How many liters of 0.154 M Ba(OH)2 solution contain 1.24 moles Ba(OH)2?
21A.
(1) 0.154 M = (0.154 mol Ba(OH)2 / 1 liter)
(2)
1.24 mol
(1 liter)
Volume = ------------ x ------------- = 8.05 L
1
(0.154 mol)
22. How much 5.0 M RbNO3 is needed to make 0.585 L of 1.2 M RbNO3 solution?
22A.
Given: MI = 5.0 M, MF = 1.2 M, VF = 0.585 L
Find: VI
(1) MIVI = MF VF
(2) VI = MFVF/ MI
(3) VI = (1.2 M)(0.585 L) / (5.0 M)
(4) VI = 1.40 x 10-1 L
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CHEMISTRY