Chapter 6: Solutions 1. Which statement concerning solutions is FALSE? A) A solution is a homogenous mixture of two or more pure substances. B) A solution is composed of a solvent and one or more solutes. C) A solution has its components uniformly distributed throughout the mixture. D) A solution is likely to form when the solute and the solvent have similar polarities. E) A solution forms when the solvent and the solute react to form a new substance with one uniform phase. 2. A solution contains 1.65 g of NaF in a total volume of 150.0 mL. What is its concentration expressed as % (m/V)? A) 0.011% B) 1.10% C) 11.0% D) 110% E) 1110% 3. A solution contains the label 0.2 M KNO3. What is the correct interpretation of this concentration? A) There are 0.2 moles of KNO3 in 100 mL of water. B) There are 0.2 g of KNO3 in 100 mL of solution. C) There are 0.2 molecules of KNO3 in 1 L of solution. D) There are 0.2 g of KNO3 in 1 L of water. E) There are 0.2 moles of KNO3 in 1 L of solution. 4. If 5.20 g of HCl is added to enough distilled water to form 3.00 L of solution, what is the molarity of the solution? [Molecular weight: HCl, 36.46 amu] A) 0.0475 M B) 0.143 M C) 0.428 M D) 1.73 M E) 2.34 M 5. Enough water is added to 50.0 mL of a 0.660 M NaOH solution in order to bring the total volume to 450.0 mL. What is the molarity of this diluted solution? A) 0.0330 M B) 0.0733 M C) 0.594 M D) 5.94 M E) 0.660 M; the molarity remains unchanged if only solvent is added. 6. The solubility of a solute is best described as which of the following? A) the ability of the solute to dissolve in water B) the ability of the solute to dissociate into ions when dissolved in water C) the mass of solute necessary to dissolve in 1 L of water D) the maximum amount of solute that can be dissolved in a specified amount of solvent E) the moles of solute that can dissolve in 1 L of solution Page 59 7. What mass of glucose is contained in 500.0 mL of a 5.00% (m/V) solution? A) 5.00 g B) 25.0 g C) 250 g D) 50.0 g E) 55.0 g 8. How many moles of KCl are present in 50.0 mL of a 0.552 M solution? A) 0.0276 mol B) 0.0906 mol C) 11.0 mol D) 35.2 mol E) 50.6 mol 9. Which diagram best represents the composition of an aqueous calcium chloride (CaCl2) solution? (water molecules are not shown) A) B) C) D) E) A B C D E 10. The solubility of gases in liquids is highest at _____________________. A) low temperature and low pressure B) low temperature and high pressure C) high temperature and low pressure D) high temperature and high pressure E) high pressure; temperature is immaterial 11. Calculate the concentration (% m/V) of NaCl solution that was made by dissolving 15.0 g of sodium chloride in enough water to make 300.0 mL of solution. A) 50.0% (m/V) D) 35.6% (m/V) B) 0.0500% (m/V) E) 5.00% (m/V) C) 0.356% (m/V) 12. Calculate the mass in grams of NaCl that is present in 500.0 mL of a 0.900% (m/V) solution. A) 50.0 g B) 0.500 g C) 5.00 g D) 45.0 g E) 4.50 g 13. What volume of a 0.1250 M KCl solution contains 2.330 g of KCl? [Formula weight: KCl, 74.55 amu] A) 0.2913 L B) 26.95 mL C) 25.00 mL D) 1.500 L E) 250.0 mL 14. A student needs to prepare 250.0 mL of a 2.50 M HCl solution using the stock solution 12.0 M HCl. What volume of 12.0 M HCl is required for this dilution? A) 12.0 mL B) 25.0 mL C) 52.1 mL D) 5.21 mL E) 2.50 mL 15. Which statement is FALSE? A) Water-soluble ionic compounds are electrolytes. B) NaCl is an electrolyte. C) Nonelectrolytes do not dissociate when dissolved in water. D) Ionic compounds are typically insoluble in water. E) When KI dissolves in water, the solution conducts electricity. 16. An unknown amount of water is added to 75 mL of a 3.5 M sodium chloride solution. What can be said for certain about the concentration of the solution that results? A) The concentration of the resulting solution will be less than 3.5 M. B) The concentration of the resulting solution will be greater than 3.5 M. C) The concentration of the resulting solution will be 0.26 M. D) The concentration of the resulting solution will be 3.5 M because the amount of glucose has not changed. E) It is impossible to say anything for certain about the concentration because the amount of water that was added is unknown. 17. What is the molarity of a solution that contains 4.50 mol of NaF dissolved in 750.0 mL of solution? A) 166 M B) 0.167 M C) 0.006 M D) 6.00 M E) 3.38 M 18. Which statement concerning solution concentration is true? A) A 1.0 ppm solution is more concentrated than a 1.0% (m/m) solution. B) The ppm unit of concentration is typically used for very high concentrated solutions. C) If a solution is 12% (m/m) it will also be 12% (m/V). D) If a bottle is labeled 0.10 M Ba(OH)2, the concentration of OH– ions in solution is 0.20 M. E) A solution that is 1 ppt is less concentrated than a solution that is 1 ppm. 19. Which statement concerning solutions is FALSE? A) Colloidal suspensions are solutions. B) Solutions consist of solutes and solvents. C) Solutions can have the solid, liquid, or gas state. D) Solutions are homogeneous mixtures. E) Solutes can be ionic or covalent. 20. Cardiac arrest victims are sometimes treated by injection of a calcium chloride solution directly into the heart muscle. If 2.0 mL of a 5.0% (m/V) CaCl2 solution is administered to a patient, what mass of CaCl2 was provided? A) 1.0 mg B) 10 mg C) 0.10 g D) 10 g E) 2.5 g 21. A chemist needs 0.725 moles of acetic acid for a particular reaction. What volume of a 1.50 M acetic acid solution is needed to provide this amount? A) 967 mL B) 1.09 L C) 0.967 L D) 0.483 L E) 1.09 mL 22. Change in pressure has very little effect on the solubility of solids in liquids. 23. The solubility of solids in water usually increases with increasing temperature. 24. The solubility of gases in liquids increases with increasing pressure. 25. A solution that is 1 ppm contains more dissolved solute than one that is 1 ppt.