Chapter 7: Solutions and Colloids
2.
REVIEW QUESTIONS
A solution is made by dissolving a small amount of salt in a beaker of water.
The water is referred to as the _________________.
The salt is referred to as the ________________.
Can a solution have more than one solute or only one? Explain or give an example to support your answer.
3.
Does water always have to be the Solvent in a solution?
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5.
Label the following as a homogeneous mixture or heterogeneous mixture
a. water and sand
b. vinegar and glucose
c. oil and vinegar
d. calcium carbonate and water
Describe a saturated solution and the process of making a saturated solution.
6.
How would the process be different in making a supersaturated solution?
7.
A solution is produced in which water is the solvent and there are 3 solutes. What can be done to help the
solutes dissolve faster?
a. oxygen
b. argon
c. sodium bicarbonate
What would happen to the CO2 gas in a water solution when the following treatments have been applied?
a. Cool the solution
b. Boil the solution
Iodine, I2, is very slightly soluble in water, a polar solvent, but quite soluble in toluene, a nonpolar solvent.
What can be inferred about the nature of the I2 molecule?
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10. As NH4NO3 dissolves in water, the resulting solution becomes colder. Which of the following expressions is
most correct?
a. NH4NO3→NH + NO + heat
c.
NH4NO3→NH + NO
b.
heat + NH4NO3→NH + NO
d. NH4NO3 + heat→NH + NO + heat
11. A solution is made by dissolving 25.34 grams of NaCl in enough distilled water to give a final volume of 3.00
L. What is the molarity of the solution?
12. What is the molarity of a solution containing 0.555 moles of solute in 150 mL of solution?
13. A solution is made by combining 4.00 g of sugar and 250 mL of water (density = 1.00 g/mL). What is the
concentration in % (w/w)?
14. What volume of a 30.00% (w/v) solution of sugar is needed to provide 6.00 g of sugar?
15. A solution is made by dissolving 50.0 mL of oil in enough gasoline to give 150.0 mL of solution. What is the %
(v/v) of oil in the solution?
16. How many grams of solid KCl are needed to prepare 500 mL of 0.250 M solution?
17. How many mL of 8.00 M HCl are needed to prepare 2500 mL of 0.500 M HCl solution?
18. Calculate the number of moles of ZnCl2 in 500 mL of 1.50 M solution.
19. A solution is prepared by adding 20.0 mL of 2.44 M AlCl3 solution to a flask, and then adding enough water
to give a final volume of 300.0 mL. What is the molarity of the solution?
20. An isotonic salt solution is 0.78% (w/w) NaCl in water. How many grams of NaCl are contained in 1.50 kg of
such a solution?
21. What volume of ethyl alcohol is contained in 55 mL (1 oz.) of 75 proof liquor, which is 33% (v/v) alcohol?
22. How does the boiling point of a solution of sugar water compare to the boiling point of pure water? Vapor
Pressure? Freezing Point?
23. How does the vapor pressure of a pure solvent compare to a solution?
24. If two solutions with concentrations of 2% sugar and 4% sugar, respectively, are separated by a
semipermeable membrane. During osmosis what will happen?
25. A solution is prepared by dissolving 12.66 g of KCl in enough distilled water to give 500 mL of solution. KCl is
a strong electrolyte. How will the freezing point of the solution be different from that of pure water? Note:
Kf for water is 1.86˚C/M.
26. What is the osmotic pressure of a 0.150 M solution of AlCl3 in water that is at 0.00˚C? Consider AlCl3 to be a
strong electrolyte.
27. Describe the parts of a solution. What parts of a colloid represent similar functions for a solution
component and a colloid component?
28. Fog is a colloid. What is the dispersed phase and what is the dispersion medium?
29. What are the two things that can stabilize a colloid and prevent suspended particles from settling?
30. What passes through both osmotic and dialysis membranes?
31. What is the underlying principle involved in dialysis?
32. Find the concentration of solution in terms of molarity: 8.00 L of solution contains 3.75 mol of solute.
33. What are the 3 colligative properties? What do colligative properties all depend on?
34. Describe the Tyndall Effect.