Final S2 (2011) - Practice Test - Ch 11, 12, 13, 14, 15, 16, 18, 19, 22, 23

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1 Final S2 (2011) - Practice Test - Ch 11, 12, 13, 14, 15, 16, 18, 19, 22, 23 Multiple Choice Identify the choice that best completes the statement or answers the question. 1. If 12.0 g of a gas at 2.5 atm dissolve in 1.0 L of water at 25 C, how much will dissolve in 1. L of water at STP? 0.21 g/l 4.8 g/l 2.1 g/l 12.0 g/l 2. What is a common mean of identifying a supersaturated solution? precipitation dissolution solvation hydration 3. What volume of 12.6M HCl must be added to sufficient water to prepare 5.00 liters of 3.00M HCl? 1.19 L L 21.0 L 7.56 L 4. Calculate the freezing point of a solution that contains 8.0 g of sucrose (C 12 H 22 O 11 ) in 100 g of H 2 O. K f for H 2 O = 1.86ºC/m ºC -0.39ºC -0.22ºC -0.44ºC 5. What is the final temperature of a mixture of chromium metal and water when 50.0 grams of chromium at 15ºC (specific heat = J/(g ºC)) is added to 25 ml of water (specific heat = 4.18 J/(g ºC)) at 45ºC? The density of water is 1 g/ml. 25ºC 35ºC 30ºC 40ºC 6. When the system A + B <---> C + D is at equilibrium,. The forward reaction has stopped both the forward and reverse reactions have stopped the reverse reaction has stopped neither the forward nor the reverse reaction has stopped, but are equal 7. Which of these is a product of the first step in the ionization of phosphoric acid, H 3 PO 4? H 3 PO 4 HPO 4 2-

2 H 2 PO 4 1- PO Which of the following is a weak acid? HCl HClO 4 HNO 3 HF 9. Why is it possible to derive the ion product constant for water, but not for aqueous acids? At a given temperature, aqueous acids have constant concentrations. The concentration of pure water is constant. Aqueous acids never reach equilibrium. Water does not ionize completely. 10. Neutralization is the chemical process in which. sodium ions react with chloride ions to form sodium chloride hydrogen ions react with chloride ions to form hydrogen chloride 11. This is the expression for the equilibrium constant for the reaction: sodium ions react with hydroxide ions to form sodium hydroxide hydrogen ions react with hydroxide ions to form water Data related to aqueous solutions of sodium chloride (NaCl) and aqueous solutions of ethanol (C 2 H 5 OH) are provided in the table below. Use the table to answer the following questions. Choose the letter of the choice that best answers the question. Mass (g) Volume (ml) Solution NaCl H 2 O Solution C 2 H 5 OH H 2 O Which of the following solutions is the most dilute? Solution 1 Solution 3 Solution 2 Solution Which of the following dissociates entirely into metal ions and hydroxide ions in solution? a strong acid a weak acid a strong base a weak base 14. Which of the following represents a Brønsted-Lowry conjugate acid-base pair?

3 SO and SO H O and H CO and CO NH and NH 15. What characterizes a strong acid or base? polar covalent bonding complete ionization in water ionic bonding presence of a hydroxide or hydrogen ion 16. What is the nature of a covalent bond in alkanes? Ionic Nonpolar covalent Polar covalent Metallic 17. The name of a compound with the functional group OH has the suffix ol. oic aci al. one. 18. Which of the following compounds is trichloromethane? 19. Aldehydes have the general structure. 20. The IUPAC name of is 2-hexyne 2-hexanol 2-hexene 4-hexyne 21. Copper is one of a group of metals called the coinage metals. How many atoms of copper (Cu) are in a pure copper coin weighing 12.0 g? atoms atoms atoms atoms 22. How many grams of water are produced when 2.50 mol oxygen reacts with hydrogen? g 45.0 g 22.5 g 90.0 g 23. In the reaction 2CO(g) + O (g) 2CO (g), what is the ratio of moles of O used to moles of CO produced? 1:1 1:2

4 2:1 2:2 24. When glucose is consumed, it reacts with oxygen in the body to produce carbon dioxide, water, and energy. How many grams of carbon dioxide would be produced if 45 g of C H O completely reacted with oxygen? 1.5 g 11 g 1.8 g 66 g 25. In the chemical equation H O (aq) H O(l) O (g), the is a. catalyst product solid reactant 26. What is the mole ratio of O 2 to phosphorus(v) oxide in the reaction P 4 (s) + 5O 2 (g) P 4 O 10 (s)? 1:1 5:1 1:5 4: For the reaction 2Na + Cl 2 2NaCl, calculate the % yield if 200. g of chlorine react with excess sodium to produce 240. g of sodium chloride. 61.2% 83.4% 72.8% 88.4% 28. Each of the four types of reaction stoichiometry problems requires using a table of bond energies. Lewis structure. chart of electron configurations. mole ratio. 29. For the reaction represented by the equation C + 2H 2 CH 4, how many moles of hydrogen are required to produce 10 mol of methane, CH 4? 2 mol 10 mol 4 mol 20 mol 30. For the reaction represented by the equation 2Na + Cl 2 2NaCl, how many grams of chlorine gas are required to react completely with 2.00 mol of sodium? 35.5 g g 70.9 g g 31. For the reaction represented by the equation Cl 2 + 2KBr 2KCl + Br 2, how many grams of potassium chloride can be produced from 300. g each of chlorine and potassium bromide? 98.7 g 188 g 111 g 451 g 32. If the % yield is equal to 100%, then the actual yield is greater than the theoretical yiel the actual yield is equal to the theoretical yiel the actual yield is less than the theoretical yiel there was no limiting reactant. 33. What is the ratio between the coefficients of any two substances in a balanced equation? molar mass balanced equation quadratic equation mole ratio chemical formula 34. Based on the following equation, how many moles of hydrochloric acid are needed to react with 0.64 moles of potassium permanganate? 2KMnO HCl Æ 3 Cl MnO H 2 O + 2KCl 0.21 mol HCl 2.7 mol HCl

5 0.64 mol HCl 5.1 mol HCl 35. What is the percent yield for the reaction between 9.8 grams of Ca(OH) 2 and 9.8 grams of H 3 PO 4 when 2.5 grams of Ca 3 (PO 4 ) 2 are actually obtained? 3Ca(OH) 2 + 2H 3 PO 4 Æ Ca 3 (PO 4 ) 2 + 6H 2O 19% 9% 27% 36% 36. According to the kinetic theory, collisions between molecules in a gas. are perfectly elastic never occur are inelastic cause a loss of total kinetic energy 37. What causes gas pressure in a container such as a helium balloon? the walls of the container the vacuum maintained in the container the simultaneous collisions of fast-moving particles in the container atmospheric pressure acting on the outside walls of the container 38. What happens to the volume of a gas during compression? The volume increases. The volume decreases. The volume remains constant. It is impossible to tell because all gases are different. 39. A sample of a gas has a pressure of 3.00 atm at 25 C. What would the gas pressure be at 52 C, if the volume remains constant? 1.44 atm 3.27 atm 2.75 atm 6.24 atm 40. A 1.00 L sample of a gas has a mass of 1.92 g at STP. What is the molar mass of the gas? 1.92 g/mol 22.4 g/mol 19.2 g/mo 43.0 g/mol 41. Convert the pressure atm to mm Hg. 365 mm Hg 638 mm Hg 437 mm Hg 780 mm Hg 42. A mixture of four gases exerts a total pressure of 860 mm Hg. Gases A and B each exert 220 mm Hg. Gas C exerts 110 mm Hg. What pressure is exerted by gas D? 165 mm Hg 860 mm Hg 310 mm Hg 220 mm Hg 43. The volume of a gas is 5.0 L when the temperature is 5.0ºC. If the temperature is increased to 10.0ºC without changing the pressure, what is the new volume? 2.5 L 5.1 L 4.8 L 10.0 L 44. The volume of a gas collected when the temperature is 11.0ºC and the pressure is 710 mm Hg measures 14.8 ml. What is the calculated volume of the gas at 20.0ºC and 740 mm Hg? 7.8 ml 14.6 ml 13.7 ml 15 ml 45. The standard molar volume of a gas at STP is 22.4 L. g-mol wt/22.4 L. g/22.4 L. 1 L.

6 46. What is the pressure exerted by 1.2 mol of a gas with a temperature of 20.ºC and a volume of 9.5 L? atm 3.0 atm 1.0 atm 30. atm Use the table below to answer the following questions. Element Atomic Mass Argon Bromine Carbon Chlorine Fluorine Helium Hydrogen Nitrogen Oxygen How many times greater is the rate of effusion of molecular fluorine than that of molecular bromine at the same temperature and pressure? How many times greater is the rate of effusion of oxygen gas than that of carbon dioxide gas at the same temperature and pressure? A sample of helium diffuses 4.57 times faster than an unknown gas diffuses. What is the molar mass of the unknown gas? 12 g/mol 38.8 g/mol 18.2 g/mol 83.5 g/mol 50. A sample of hydrogen gas diffuses 3.8 times faster than an unknown gas diffuses. What is the molar mass of the unknown gas? 4.0 g/mol 22 g/mol 7.6 g/mol 29 g/mol 51. The theory that describes the behavior of gases in terms of the motion of gas particles is. the theory of intermolecular forces Dalton s law of parhal pressures Graham s law of effusion the kinetic-molecular theory 52. Which of the following molecules can form hydrogen bonds? BaH 3 CH 3 NaH 3 NH What is the name given to the relationship that shows that an increase in pressure leads to a decrease in the volume of a gas? Charles s law Avogadro s number

7 Boyle s law Gay-Lussac s law 54. What volume will 1.80 mol of gas occupy at STP? 0.25 L 3.34 L 12.4 L 40.4 L 55. How many grams of ammonia (NH 3 ) are present in a sample that occupies 2.0 L at a pressure at 2.0 atm and 25 C? grams 2.79 grams 6.33 grams grams 56. Calculate the number of moles of gas contained in a 16.0-L vessel at 373 K with a pressure of 2.50 atm. 2.8 x 10-3 mol mol 1.31 x 10-1 mol 1.31 mol

8 Final S2 (2011) - Practice Test - Ch 11, 12, 13, 14, 15, 16, 18, 19, 22, 23 Answer Section MULTIPLE CHOICE 1. ANS: C PTS: 1 2. ANS: A PTS: 1 3. ANS: A PTS: 1 4. ANS: D PTS: 1 5. ANS: D PTS: 1 6. ANS: D PTS: 1 7. ANS: B PTS: 1 8. ANS: D PTS: 1 9. ANS: A PTS: ANS: D PTS: ANS: B PTS: ANS: D PTS: ANS: B PTS: ANS: D PTS: 1 DIF: L2 REF: p. 591 OBJ: STA: Ch.5.e 15. ANS: B PTS: 1 DIF: L1 REF: p. 605 OBJ: STA: Ch.5.c 16. ANS: C The difference in the electronegativity of carbon and hydrogen is very small (0.35). A B C D Feedback Ionic bonds are formed by the transfer of electrons. Polar covalent bonds are formed in compounds in which the difference in electronegativity of atoms is high. Correct! Metallic bonds are found in metals only. PTS: 1 DIF: 2 REF: Page 708 OBJ: Describe the properties of alkanes. NAT: B.2 TOP: Describe the properties of alkanes. KEY: Nature of bond in alkanes MSC: ANS: A PTS: 1 DIF: II OBJ: STA: 10e* 18. ANS: A PTS: 1 DIF: L2 REF: p. 728 OBJ: ANS: B PTS: 1 DIF: L1 REF: p. 737 OBJ: STA: Ch.10.e 20. ANS: A PTS: ANS: D

9 A B C D Feedback Instead of dividing, multiply the calculated number of moles of copper by Avogadro's number. Multiply the calculated number of moles of copper by Avogadro's number. The molar mass of copper is 63.5 g/mol Correct! PTS: 1 DIF: 2 REF: Page 317 OBJ: Calculate the number of atoms of an element when given the number of moles of the element. NAT: UCP.3 B.1 TOP: Calculate the number of atoms of an element when given the number of moles of the element. KEY: Mass to atoms conversion MSC: ANS: D The balanced chemical equation is. A B C D Feedback Multiply the number of moles of water by the molar mass of water. Multiply the number of moles by the mole ratio. Balance the equation correctly. Correct! PTS: 1 DIF: 3 REF: Page 360 OBJ: Use the steps to solve stoichiometric problems. NAT: UCP.1 UCP.3 B.3 STA: 3e TOP: Use the steps to solve stoichiometric problems. KEY: Stoichiometric mole-to-mass conversion MSC: ANS: C PTS: 1 DIF: L1 REF: p. 356 OBJ: STA: Ch.4.c 24. ANS: D PTS: 1 DIF: L2 REF: p. 360 p. 361 p. 362 OBJ: STA: Ch.3.d 25. ANS: C PTS: 1 DIF: L1 REF: p. 323 OBJ: STA: Ch.3.a 26. ANS: C PTS: 1 DIF: I OBJ: STA: 3e 27. ANS: B PTS: 1 DIF: II OBJ: STA: 3f* 28. ANS: D PTS: 1 DIF: I REF: 1 OBJ: ANS: D PTS: 1 DIF: III REF: 1 OBJ: ANS: B PTS: 1 DIF: III REF: 2 OBJ: ANS: C

10 Since Cl 2 would produce the most KCl, KBr is the limiting reactant, thus 188 G KCl is produce PTS: 1 DIF: III REF: 2 OBJ: ANS: B PTS: 1 DIF: I REF: 3 OBJ: ANS: B PTS: ANS: C PTS: ANS: A PTS: ANS: A PTS: 1 DIF: L1 REF: p. 385 OBJ: STA: Ch.4.a 37. ANS: C PTS: 1 DIF: L2 REF: p. 386 OBJ: STA: Ch.4.a 38. ANS: B PTS: 1 DIF: I OBJ: STA: 4b 4d 39. ANS: C PTS: 1 DIF: I OBJ: STA: 4c 40. ANS: D PTS: 1 DIF: II OBJ: ANS: C PTS: 1 DIF: II REF: 1 OBJ: ANS: B PTS: 1 DIF: III REF: 1 OBJ: ANS: C PTS: 1 DIF: III REF: 2 OBJ: ANS: C PTS: 1 DIF: III REF: 2 OBJ: ANS: A PTS: 1 DIF: I REF: 3 OBJ: ANS: C

11 PTS: 1 DIF: III REF: 3 OBJ: ANS: A PTS: 1 DIF: III REF: 4 OBJ: ANS: A PTS: 1 DIF: III REF: 4 OBJ: ANS: D PTS: 1 DIF: III REF: 4 OBJ: ANS: D PTS: 1 DIF: III REF: 4 OBJ: ANS: D PTS: ANS: D PTS: ANS: B PTS: ANS: D PTS: ANS: C PTS: ANS: D PTS: 1