Unit 13 Practice Test

Transcription

1 Name: Class: Date: Unit 13 Practice Test Multiple Choice Identify the choice that best completes the statement or answers the question. 1) The dissolution of water in octane (C 8 H 18 ) is prevented by. A) London dispersion forces between octane molecules B) hydrogen bonding between water molecules C) dipole-dipole attraction between octane molecules D) ion-dipole attraction between water and octane molecules E) repulsion between like-charged water and octane molecules 2) Hydration is a specific example of the phenomenon known generally as. A) salutation B) disordering C) solvation D) condensation E) dilution 3) Compounds composed of a salt and water combined in definite proportions are known as. A) clathrates B) homogenates C) ionic solids D) molecular solids E) hydrates 4) The principal reason for the extremely low solubility of NaCl in benzene (C 6 H 6 ) is the. A) strong solvent-solvent interactions B) hydrogen bonding in C 6 H 6 C) strength of the covalent bond in NaCl D) weak solvation of Na + and Cl by C 6 H 6 E) increased disorder due to mixing of solute and solvent 5) Which of the following substances is more likely to dissolve in CH 3 OH? A) CCl 4 B) Kr C) N 2 D) CH 3 CH 2 OH E) H2 6) Which one of the following substances is more likely to dissolve in benzene (C 6 H 6 )? A) CH 3 CH 2 OH B) NH 3 C) NaCl D) CCl 4 E) HBr 1

2 Name: 7) The solubility of nitrogen gas at 25 C and 1 atm is mol/l. If the partial pressure of nitrogen gas in air is 0.76 atm, what is the concentration (molarity) of dissolved nitrogen? A) M B) M C) M D) M E) M 8) Which of the following statements is false? A) Nonpolar liquids tend to be insoluble in polar liquids. B) The weaker the attraction between the solute and solvent molecules, the greater the solubility. C) Substances with similar intermolecular attractive forces tend to be soluble in one another. D) The solubility of a gas increases in direct proportion to its partial pressure above the solution. E) The solubility of gases in water decreases with increasing temperature. 9) Calculate the molarity of a 10.0% (by mass) aqueous solution of hydrochloric acid. A) m B) 2.74 m C) 3.04 m D) 4.33 m E) The density of the solution is needed to solve the problem. 10) Which one of the following concentration units varies with temperature? A) molarity B) mass percent C) mole fraction D) molality E) all of the above 11) A m solution of which one of the following solutes will have the lowest vapor pressure? A) KClO 4 B) Ca(ClO 4 ) 2 C) Al(ClO 4 ) 3 D) sucrose E) NaCl 12) Which of the following liquids will have the lowest freezing point? A) pure H 2 O B) aqueous glucose (0.60 m) C) aqueous sucrose (0.60 m) D) aqueous FeI 3 (0.24 m) E) aqueous KF (0.50 m) 2

3 Name: 13) A 1.35 m aqueous solution of compound X had a boiling point of C. Which one of the following could be compound X? The boiling point elevation constant for water is 0.52 C/m. A) CH 3 CH 2 OH B) C 6 H 12 O 6 C) Na 3 PO 4 D) KCl E) CaCl 2 14) The most likely van't Hoff factor for an 0.01 m CaI 2 solution is. A) 1.00 B) 3.00 C) 1.27 D) 2.69 E) ) Calculate the vapor pressure of a solution made by dissolving 109 grams of glucose (molar mass = g/mol) in ml of water at 25 C. The vapor pressure of pure water at 25 C is mm Hg. Assume the density of the solution is 1.00 g/ml. A) mm Hg B) mm Hg C) mm Hg D) mm Hg E) mm Hg 16) Which of the following cannot be a colloid? A) an emulsion B) an aerosol C) a homogeneous mixture D) a foam E) All of the above are colloids. 17) The solubility of Ar in water at 25 C is M when the pressure of the Ar above the solution is 1.0 atm. The solubility of Ar at a pressure of 2.5 atm is M. A) B) C) D) E) ) The solubility of MnSO 4 monohydrate in water at 20 C is 70.0 g per ml of water. A solution at 20 C that is 4.22 M in MnSO 4 monohydrate is best described as a(n) solution. The formula weight of MnSO 4 monohydrate is g/mol. A) hydrated B) solvated C) saturated D) unsaturated E) supersaturated 3

4 Name: 19) A solution is prepared by dissolving 23.7 g of CaCl 2 in 375 g of water. The density of the resulting solution is 1.05 g/ml. The concentration of Cl in this solution is M. A) B) C) 1.12 D) 1.20 E) ) The concentration of HCl in a solution that is prepared by dissolving 5.5 g of HCl in 200 g of C 2 H 6 O is molal. A) 27.5 B) C) D) 0.75 E) ) The concentration of urea (MW = 60.0 g/mol) in a solution prepared by dissolving 16 g of urea in 39 g of H 2 O is molal. A) 96 B) 6.8 C) 0.68 D) 6.3 E) ) What is the mole fraction of sodium chloride in solution that is 13.0% by mass sodium chloride and that has a density of 1.10 g/ml? A) B) C) D) E) ) A solution containing 10.0 g of an unknown liquid and 90.0 g water has a freezing point of 3.33 C. Given K f = 1.86 C/m for water, the molar mass of the unknown liquid is g/mol. A) 69.0 B) 333 C) 619 D) 161 E) ) An aqueous solution of a soluble compound (a nonelectrolyte) is prepared by dissolving 33.2 g of the compound in sufficient water to form 250 ml of solution. The solution has an osmotic pressure of 1.2 atm at 25 C. What is the molar mass (g/mole) of the compound? A) B) C) D) E) 28 4

5 Name: 25) A saturated solution. A) contains dissolved solute in equilibrium with undissolved solute B) has the capacity to dissolve more solute C) will rapidly precipitate if a seed crystal is added D) contains no double bonds E) cannot be attained 26) The solubility of oxygen gas in water at 25 C and 1.0 atm pressure of oxygen is g/l. The solubility of oxygen in water at 4.0 atm and 25 C is g/l. A) B) C) 0.31 D) 0.16 E) ) The concentration of urea in a solution prepared by dissolving 16 g of urea in 25 g of H 2 O is % by mass. The molar mass of urea is 60.0 g/mol. A) 39 B) 64 C) 0.39 D) 0.64 E) ) Calculate the mole fraction of phosphoric acid (H 3 PO 4 ) in a 38.5% (by mass) aqueous solution. A) B) C) D) E) The density of the solution is needed to solve the problem. 29) Calculate the mole fraction of nitric acid of an 8.37% (by mass) aqueous solution of nitric acid. A) B) C) D) E) The density of the solution is needed to solve the problem. 30) The concentration of lead nitrate (Pb(NO 3 ) 2 ) in a M solution is molal. The density of the solution is g/ml. A) B) 2.13 C) 1.03 D) E)

6 Name: 31) At 20 C, a 3.13 M aqueous solution of ammonium chloride has a density of g/ml. What is the molality of ammonium chloride in the solution? The formula weight of NH 4 Cl is g/mol. A) 3.56 B) C) 3.13 D) E) ) Calculate the molarity of phosphoric acid (H 3 PO 4 ) in a 22.1% (by mass) aqueous solution. A) m B) m C) m D) m E) The density of the solution is needed to solve the problem. 33) Calculate the molality of a 35.0% (by mass) aqueous solution of nitric acid. A) 6.64 B) 538 C) 2.19 D) 3.32 E) The density of the solution is needed to solve the problem. 34) The concentration of lithium chlorate solution is 12.0% by mass. In a g sample of this solution, there are g of dissolved lithium chlorate. A) 1990 B) 28.6 C) D) 5.03 E) ) Which of the following will have an ideal van't Hoff factor (i) value of 1? A) sucrose B) NaF C) LiNO 3 D) NH 4 NO 3 E) Li 2 PO 4 36) Calculate the freezing point of a m aqueous solution of NaNO 3. The molal freezing-point-depression constant of water is 1.86 C/m. A) B) C) D) E)

7 Name: 37) The osmotic pressure of a solution formed by dissolving 45.0 mg of aspirin C 9 H 8 O 4 ) in L of water at 25 C is atm. A) 24.5 B) C) D) 4.41 E)

8 Unit 13 Practice Test Answer Section MULTIPLE CHOICE 1) ANS: B PTS: 1 DIF: 2 REF: Page Ref: ) ANS: C PTS: 1 DIF: 1 REF: Page Ref: ) ANS: E PTS: 1 DIF: 2 REF: Page Ref: ) ANS: D PTS: 1 DIF: 2 REF: Page Ref: ) ANS: D PTS: 1 DIF: 2 REF: Page Ref: ) ANS: D PTS: 1 DIF: 2 REF: Page Ref: ) ANS: B PTS: 1 DIF: 4 REF: Page Ref: 13.3 OBJ: 13.3; G4 8) ANS: B PTS: 1 DIF: 2 REF: Page Ref: 13.3 OBJ: 13.3; G2 9) ANS: E PTS: 1 DIF: 3 REF: Page Ref: ) ANS: A PTS: 1 DIF: 3 REF: Page Ref: 13.4 OBJ: 13.4; G2 11) ANS: C PTS: 1 DIF: 2 REF: Page Ref: ) ANS: E PTS: 1 DIF: 2 REF: Page Ref: ) ANS: D PTS: 1 DIF: 3 REF: Page Ref: ) ANS: D PTS: 1 DIF: 3 REF: Page Ref: ) ANS: D PTS: 1 DIF: 3 REF: Page Ref: 13.5 OBJ: 13.5; G4 16) ANS: C PTS: 1 DIF: 2 REF: Page Ref: ) ANS: C PTS: 1 DIF: 2 REF: Page Ref: 13.3 OBJ: 13.3; G4 18) ANS: E PTS: 1 DIF: 3 REF: Page Ref: 13.3 OBJ: 13.2; G3 19) ANS: C PTS: 1 DIF: 4 REF: Page Ref: ) ANS: D PTS: 1 DIF: 3 REF: Page Ref: ) ANS: B PTS: 1 DIF: 3 REF: Page Ref:

9 22) ANS: A PTS: 1 DIF: 4 REF: Page Ref: ) ANS: E PTS: 1 DIF: 4 REF: Page Ref: 13.5 OBJ: 13.5; G4 24) ANS: B PTS: 1 DIF: 4 REF: Page Ref: 13.5 OBJ: 13.5; G4 25) ANS: A PTS: 1 DIF: 1 REF: Page Ref: 13.2 OBJ: 13.2; G2 26) ANS: D PTS: 1 DIF: 2 REF: Page Ref: 13.3 OBJ: 13.3; G4 27) ANS: A PTS: 1 DIF: 3 REF: Page Ref: ) ANS: A PTS: 1 DIF: 4 REF: Page Ref: ) ANS: A PTS: 1 DIF: 3 REF: Page Ref: ) ANS: C PTS: 1 DIF: 5 REF: Page Ref: ) ANS: A PTS: 1 DIF: 4 REF: Page Ref: ) ANS: E PTS: 1 DIF: 3 REF: Page Ref: ) ANS: A PTS: 1 DIF: 3 REF: Page Ref: ) ANS: A PTS: 1 DIF: 4 REF: Page Ref: ) ANS: A PTS: 1 DIF: 4 REF: Page Ref: ) ANS: E PTS: 1 DIF: 4 REF: Page Ref: 13.5 OBJ: 13.5; G4 37) ANS: C PTS: 1 DIF: 4 REF: Page Ref: 13.5 OBJ: 13.5; G4 2

10 Unit 13 Practice Test [Answer Strip] ID : A _ B 7) _ D 13) _ C 19) _ A 25) _ B 1) _ B 8) _ D 14) _ D 20) _ D 26) _ C 2) _ E 9) _ D 15) _ B 21) _ A 27) _ E 3) _ A 10) _ C 16) _ A 22) _ A 28) _ D 4) _ C 11) _ C 17) _ E 23) _ A 29) _ D 5) _ C 30) _ D 6) _ E 12) _ E 18) _ B 24)

11 Unit 13 Practice Test [Answer Strip] ID : A _ A 31) _ C 37) _ E 32) _ A 33) _ A 34) _ A 35) _ E 36)