Unit 11 Review

1. How do you call the dissolving medium in a solution?

a. Solventb. Solutec. Electrolyted. Solvator

2. A hygroscopic substance that removes water from the atmosphere is called a(n)

A. surfactantB. soluteC. electrolyteD. desiccant

3. Why are 2 polar substances able to dissolve in each other?

A. There is no attractive force between themB. They react with each other.C. They have similar attractive forces between them.D. Polar substances can not dissolve in each other.

4. Which of the following substances is most soluble in water?

A. OilB. ParaffinC. Sodium chlorideD. Methane gas

5. Which of the following is NOT a unique property of water?

A. Low vapor pressureB. Higher density of iceC. Relatively high boiling pointD. Surface tension

6. Hydrogen bonding is caused by the attraction of the charges between

a. negative O and positive Hb. negative O and negative Hc. positive O and positive Hd. positive O and negative H

7. Which of the following statements are true?

• I. The particle size in colloids is larger than 1000 nm.• II. Surface tension is higher in water than in rubbing alcohol.

A. Only IB. Only IIC. Both I and IID. Neither I nor II

8. A mixture in which particles eventually settle is called

a. a suspensionb. a colloidc. an electrolyted. a surfactant

9. Which of the following is NOT a factor affecting solution formation?

a. Temperatureb. Particle sizec. Volumed. Agitation

10. What is the concentration (molarity) when you dissolve 0.20 mol NaCl in 0.80 L of water?

a. 4.0 Mb. 1.0 Mc. 0.5 Md. 0.25 M

11. Which of the following statements are true?

I. Adhesion occurs between like bodies.II. Dilute solutions have a large amount of solute.

a. Only I.b. Only II.c. Both I and IId. Neither I nor II.

12. Using salt to prevent roads from icing over in winter time is an example of:

A. Freezing point elevationB. Vapor pressure depressionC. Freezing point depressionD. Vapor pressure elevation

13. When dissolving a compound in water, which of the following occurs when the temperature increases?

A. Solubility increases.B. Solubility decreases.C. Solubility remains the same.D. Not enough information to determine this.

14. Henry’s law states that when the pressure increases, the solubility of a gas in liquid a. decreasesb. stays the samec. increases

15. An example of a colloid is

A. milkB. vegetable soupC. 7-upD. sand water mixture

16. How many mL of a 0.5 M solution of KCl do you need to make 250 mL of a 0.025 M solution?

a. 250 mLb. 25 mLc. 12.5 mLd. 5 mL

17. Water and vegetable oil don’t mix because of a difference in

a. melting pointb. particle sizec. colord. polarity

18. In a concentrated solutions there is

A. no soluteB. a small amount of soluteC. a large amount of soluteD. no solvent

19. The rule “like dissolves like” is used to predict

A. densityB. melting pointC. phaseD. solubility

20. Surfactants are characterized by what?• A. They can lower surface tension• B. They help dissolve oil in water• C. They are made of a polar and a non-polar part• D. All of the above

21. When 1 particle CaCl2 dissolves in water, how many particles will it generate in the solution?

a. 1b. 2c. 3d. 4

22. What is the molality when 3.4 g NaCl is dissolved in 170 g H2O?A. 578 mB. 0.34 mC. 50. mD. 9.8 m

23. A saturated solution contains

A. The maximum amount of solute that can dissolveB. Equal amounts of solute and solventC. Particles that will eventually settleD. Dissolved ionic compounds

24. What is the percent solution (w/w) when 1.5 g KNO3 is dissolved 300 mL water?

A. 50 %B. 0.75 %C. 1.5 %D. 0.5 %

25. Which of the following is characteristic for colloids?A. The particles are smaller than 1 nm.B. Particles eventually settle.C. They scatter light.D. They conduct electricity.

Answer Key

1. A 8. A 15. A 22. B2. D 9. C 16. C 23. A3. C 10. D 17. D 24. D4. C 11. D 18. C 25. C5. B 12. C 19. D6. A 13. D 20. D7. B 14. C 21. C