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1 UNIVERSITY OF VICTORIA Sections: A01, A02 FINAL EXAMINATION CRN 20394, CHEMISTRY 102 Fundamentals of Chemistry II Instructors: R. Lipson, S. Briggs Monday APRIL 7, 2014 Duration: 3 hours This exam has a total of 20 pages + DATA sheet (inside) + optical sense (bubble) sheet (separate) Students must count the number of pages in this examination paper before starting to write the exam. Report any discrepancy immediately to one of the instructors in the room. DISPLAY YOUR STUDENT ID CARD ON THE TOP OF YOUR DESK NOW Answer all questions on the bubble sheet provided. This exam consists entirely of multiple choice questions. There are 65 multiple choice questions worth 2 marks each. TOTAL MARKS AVAILABLE = 130 This question paper contains enough blank space for working out the questions. No other paper is permitted. The answers must be coded on the optical sense form (bubble sheet) using a SOFT PENCIL. PRINT and shade in only your last name, first name, and the last 7 digits of your student ID number on the bubble sheet. i.e. Omit the leading V0. Do NOT include any information about the course, section or date on the bubble sheet. Hand in only the bubble sheet at the end of the exam period (3 hours). The basic Sharp EL510 calculator is the only one approved for use in Chemistry 102. It is a University Calendar regulation that no student may arrive at the exam after the first half hour and no student may leave the exam in the first half hour. If you finish your exam before 2¾ hours have elapsed then you may hand in your bubble sheet and leave. We ask that students not leave (i.e. that students remain seated) during the last 15 minutes of the exam so that everyone remaining may finish their exams without noise or disturbance. DO NOT BEGIN UNTIL TOLD TO DO SO BY THE INVIGILATOR

2 Chem 102, Final Exam, April 2014 Page 2 of 20 This exam consists entirely of 65 multiple choice questions and is worth 130 marks. There are two marks per question. The answers for the 65 questions must be coded on the optical sense form (bubble sheet) using a SOFT PENCIL. Select the BEST response for each question below. 1. A sample of O 2 gas with a volume of L was collected at 21 o C. Calculate the volume in liters of the gas when it is cooled to 10 o C if the gas is ideal and the pressure remains constant. A B C D E Vessel A contains CO 2 (g) at 0 C and 1 atm. Vessel B contains CH 4 (g) at 0 C and 1 atm. The two vessels have the same volume. Which of the following statement(s) is/are TRUE? (i) Vessel B contains more molecules. (ii) Vessel B contains more mass of gas. (iii) The average kinetic energy of molecules in Vessel B is higher. (iv) The root mean square (rms) speed of molecules in Vessel B is higher. A. (iv only) B. (i)&(iv) C. (iii)&(iv) D. (ii)&(iv) E. (i)&(iii) 3. Suppose 1000 moles of oxygen gas (O 2) is compressed into a steel tank that has a volume of 45.0 L. Assuming that oxygen behaves as an ideal gas, and that the temperature of the gas and tank is 0 C, calculate the pressure inside the tank in atmospheres. A B C. 498 D E The actual pressure for the real gas in the tank described above in Question 3 is 1026 atm. Explain briefly the reason for any difference between this value and the result of your calculation in part (a) above. A. Real molecules have intermolecular forces of attraction, and at high pressures this is important. B. Real molecules take up space, and at high pressures this is important. C. Real molecules have more kinetic energy at 0º C than ideal ones do. D. Real molecules are attracted to the steel tank more strongly than are ideal gas molecules. E. The ideal gas law does not take viscosity into account.

3 Chem 102, Final Exam, April 2014 Page 3 of The phase diagram for carbon dioxide (CO 2 ) is shown below (not to scale). The vertical axis is pressure in atmospheres. The horizontal axis is temperature in ºC. What is the normal boiling point (bp) of carbon dioxide? A ºC B ºC C. +25 ºC D. CO 2 doesn t have a normal boiling point. E. The normal bp doesn t show up on this graph. 6. Consider the phase diagram for carbon dioxide in Question 5 above. Which of the following statements is/are TRUE? i. Liquid CO 2 can exist at STP. ii. Solid, liquid & gas phases are all in equilibrium at 5.11 atm and ºC. iii. Separate liquid and gas phases of CO 2 can t exist above 31.0 ºC. iv. CO 2 at 5.0 atm pressure and -50 ºC is gaseous. A. (i) & (iii) only B. (i) & (iv) only C. (i), (iii) & (iv) only D. (ii)&(iv) only E. (ii), (iii), & (iv) only 7. Consider the apparatus shown in the drawing below. When the black stopcock between the two containers is opened and the gases are allowed to mix, what is the partial pressure of O 2 after mixing? N 2 O L 2.0 atm 25 o C 4.0 L 3.0 atm 25 o C A atm B. 2.5 atm C atm D. 5.2 atm E. 3.2 atm

4 Chem 102, Final Exam, April 2014 Page 4 of In an electrolysis of water experiment, 98.6 ml of H 2 gas were collected over water at 50.0 C at a total pressure of atm. The vapour pressure of water at 50.0 C is atm. What mass of H 2 was collected? A mg B mg C mg D µg E mg 9. Which one of the following gases has the lowest average molecular velocity at 350 K? A. xenon (Xe) B. oxygen (O 2 ) C. chlorine (Cl 2 ) D. carbon monoxide (CO) E. all have the same average molecular velocity. 10. For many hundreds of years drinking water has been cooled in hot climates by evaporating it from the surfaces of canvas or leather bags or clay pots. How much water can theoretically be cooled from 40 C to 20 C by the evaporation of g of water? The enthalpy of vapourization of water ( H vap ) in this temperature range is 2.4 kj g -1. A kg B kg C kg D kg E kg 11. Which of the following statements is NOT CORRECT? A. Absorption of infrared radiation increases the vibrational energy in a molecule. B. NO is formed by the direct combination of nitrogen and oxygen in internal combustion engines. C. CO 2, N 2 O and Ne are all greenhouse gases. D. Stratospheric ozone (O 3 ) absorbs ultraviolet radiation and thereby helps protect us from high-energy photons. E. SO 2 in the atmosphere is a major cause of acid rain.

5 Chem 102, Final Exam, April 2014 Page 5 of Why are chlorofluorocarbons (CFCs) so damaging to the ozone layer when they are such stable molecules? A. The radiation in the stratosphere dissociates CFCs to produce chlorine atoms which catalytically destroy ozone. B. CFCs contain a double bond that reacts with ozone, resulting in the destruction of the ozone. C. CFCs are very light molecules that rapidly diffuse into the upper atmosphere and block the radiation that causes the formation of ozone. D. CFCs are greenhouse gases that raise the atmospheric temperature above the dissociation temperature of ozone. E. CFCs do not damage the ozone. 13. A catalyst generally speeds up a chemical reaction by A. increasing the activation energy for the reverse reaction. B. shifting the position of equilibrium. C. making the reaction more exothermic D. changing to a mechanism that has a lower activation energy. E. increasing the temperature at which the reaction will proceed spontaneously. 14. Which of the following statements about water is NOT correct A. The fact that solid water floats on liquid water is important for aquatic life. B. The only treatment seawater needs to be made fit for human consumption is the addition of a chemical agent to ensure destruction of bacteria. C. Ion exchange is a procedure that replaces Ca 2+ ions in the water with Na + ions. D. Very small concentrations of lead, mercury and cadmium are toxic. E. Treatment with ozone is one method for the destruction of bacteria in water. 15. Which of the following is NOT a consequence of acid rain? A. Fish in lakes die when the ph is less that about 4.5. B. Aluminum (as Al 3+ ions) leaches into lakes due to high acidity. C. Mineral plant nutrients such as K + and Ca 2+ become more soluble in acidic conditions and are washed out of the soil. D. Acidic lakes take on a peculiar yellow colour. E. Limestone sculptures and building stones become damaged by acid rain.

6 Chem 102, Final Exam, April 2014 Page 6 of Dimethyl ether burns according to the following chemical equation: C 2 H 6 O(g) + 3O 2 (g) 2CO 2 (g) + 3H 2 O(l) ΔHº = kj Using information from the data sheet, calculate the enthalpy of formation of dimethyl ether kj/mol). A B C D E A gas is confined to a cylinder under a moveable piston at constant pressure. When the gas undergoes a particular chemical reaction, it gives off 2,500 J of heat to the surroundings and does 7,655 J of work on the surroundings. What are the values of H (in J) and E (in J) for this process? A. H = J, E = J B. H = 2500 J, E = J C. H = J, E = 2500 J D. H = 5155 J, E = 2500 J E. H = J, E = J 18. The magnitude of the absolute entropy (S) of a sample of a molecular substance is determined by A. the physical state (phase) of the substance. B. the complexity of the molecules. C. the temperature. D. the amount of the substance. E. all of the above.

7 Chem 102, Final Exam, April 2014 Page 7 of Consider the following heating curve. The heating curve shown above was generated by measuring the heat flow and temperature for a solid as it was heated. The slope of the segment corresponds to the heat capacity of the liquid of the substance. A) CD B) DE C) AB D) BC E) EF 20. The freezing of water is a spontaneous process at -5 o C at 1 atm pressure. Predict the sign (+,, or 0) of ΔG o, ΔH o and ΔS o, respectively, for this process. A., 0, + B.,, C., +, + D. 0, +, + E., +, 21. For which of the following reactions is the enthalpy of reaction equal to the enthalpy of formation of the product? A. 3 H(g) + N(g) NH 3 (g) B. 3/2 H 2 (g) + N(g) NH 3 (g) C. 3 H 2 (g) + N 2 (g) 2 NH 3 (g) D. 3/2 O 2 (g) + 2Fe (s) Fe 2 O 3 (s) E. All of the above 22. Given the following reactions: A + B C + D C + D E ΔH = kj ΔH = kj Calculate Hº rxn (kj) for the reaction 2 A + 2B 2E A. + 5 B. -10 C. +10 D. -50 E. -5

8 Chem 102, Final Exam, April 2014 Page 8 of Birch wood has a fuel value of about 18 kj g -1. How much energy is contained in a cord of birch wood (about 1 tonne, or 1000 kg)? A. 18 x 10 3 kj B. 1.8 x 10 6 kj C. 5.6 x 10 4 kj D. 18 x 10 6 kj E. 3.6 x 10 6 kj 24. Calculate S o for the combustion of methane shown below using the standard entropy data given on the Data Sheet: CH 4 (g) + 2O 2 (g) CO 2 (g) + 2H 2 O(g) A J/K B J/K C J/K D. 5.0 J/K E J/K 25. Consider the following equilibrium: 2SO 2 (g) + O 2 (g) 2 SO 3 (g) The equilibrium cannot be established when is/are placed in an empty 1.0 L container. A mol O 2 (g) and 0.50 mol SO 3 (g). B mol SO 2 (g) C. 1.0 mol SO 3 (g) D mol SO 2 (g) and 0.25 mol SO 3 (g) E mol SO 2 (g) and 0.25 mol O 2 (g) 26. At 1000K, the equilibrium constant for the reaction: C(s) + H 2 O(g) CO(g) + H 2 (g) is K P = 2.6. A closed vessel starts with a sample of solid carbon (graphite) and PH 2 O = atm, PCO = atm and PH 2 =0.804 atm at 1000K. Which one of the following statements is CORRECT? A. The reaction will go to completion (i.e. all products) since carbon is present as a solid. B. At equilibrium, the total pressure in the vessel will be less than the initial total pressure. C. The equilibrium partial pressure of CO(g) will be greater than atm. D. The equilibrium partial pressures of H 2 O, CO and H 2 will be the same as the initial values. E. The equilibrium partial pressure of H 2 O(g) will be greater than atm.

9 Chem 102, Final Exam, April 2014 Page 9 of The Sabatier reaction is an important way to use unwanted carbon dioxide in the production of water and methane. It is used on the International Space Station. Calculate (ΔH rxn ) in kj for the production of 1 mole of methane according to the chemical equation shown. CO 2 (g) + 4H 2 (g) CH 4 (g) + 2H 2 O(g) A B C D E Which statement is TRUE for a reaction that has K c = ? A. Increasing the temperature will not change the value of K c. B. There are significant concentrations of reactants and products at equilibrium. C. The reaction proceeds hardly at all toward completion. D. The reaction proceeds nearly all the way toward completion (i.e. all products). E. The reaction is endothermic. 29. Given the following hypothetical reaction: 2 A (s) + x B (g) 3 C (g) K P = 19.3 and K c = 0.45 at 523 Kelvins What is the value of the stoichiometric coefficient x? A. 1 B. 2 C. 3 D. 4 E. 5

10 Chem 102, Final Exam, April 2014 Page 10 of Consider the following reaction, the decomposition of ammonium hydrogen sulfide: NH 4 HS(s) NH 3 (g) + H 2 S(g) for which K p = at 25 o C A 5.6 g sample of NH 4 HS(s) is placed in a 1.00 L flask. What will be the partial pressure of ammonia gas (NH 3 ) when equilibrium is reached, assuming only product gases are present? A atm B atm C atm D atm E atm 31. At a certain temperature, the value of the equilibrium constant for the following reaction is K c = 100. N 2 (g) + 2 O 2 (g) 2 NO 2 (g) What is the equilibrium constant for the following reaction? 4NO 2 (g) 2N 2 (g) + 4O 2 (g) A B. 10 C D. 0.1 E An equilibrium mixture of CO, O 2, and CO 2 at a certain temperature has [CO] = M and [O 2 ] = M. At this temperature the equilibrium constant K c = CO (g) + O 2 (g) 2CO 2 (g) What is the equilibrium concentration of CO 2? A M B M C M D M E M

11 Chem 102, Final Exam, April 2014 Page 11 of Consider the following reaction: 4 HCl (g) + O 2 (g) 2 Cl 2 (g) + 2 H 2 O (g) K c = at 400 K If the reaction quotient, Q, is 0.040, which of the following statements is FALSE? A. [HCl] will increase as the reaction approaches equilibrium. B. [O 2 ] will decrease as the reaction approaches equilibrium. C. [Cl 2 ] will increase as the reaction approaches equilibrium. D. [H 2 O] will increase as the reaction approaches equilibrium. E. [HCl] will decrease as the reaction approaches equilibrium. 34. At which of the following locations will ethyl alcohol boil at the highest temperature? A. At Death Valley in California (altitude = -86m) B. On top of Mt Douglas in the northern part of Victoria near UVic. C. By the ocean at Victoria s inner harbour. D. The boiling temperature of water does not depend on the location. E. It is impossible to estimate this without a calibrated thermometer. 35. How much heat (in kj) is required to convert g water at 25.0 C into water vapour at the normal boiling point? (ΔH vap (H 2 O) is kj mol 1 ) A. 139 B C. 18,160 D E Which of the following statements is NOT CORRECT? A. A reaction at equilibrium will shift its equilibrium position if the concentrations of products are increased. B. If one starts a reaction with a higher concentration of one reactant, K eq will change. C. In an equilibrium reaction, the reverse reaction begins as soon as some product is formed. D. If a catalyst is added, the amount of product present at equilibrium is unchanged. E. If an inert gas is added to a gas reaction at equilibrium, the equilibrium is not affected.

12 Chem 102, Final Exam, April 2014 Page 12 of Which of the following statement is/are NOT CORRECT? (i) The second law of thermodynamics states that all systems become disordered spontaneously. (ii) The vaporization of a substance at its boiling point is an isothermal process. (iii) The quantity of energy gained by a system equals the quantity of energy gained by its surroundings. (iv) The entropy of a pure crystalline substance at 0 C is zero. (v) The more negative ΔG is for a given reaction, the larger the value of the corresponding equilibrium constant, K. A. (i) & (iii) B. (ii) & (iv) C. (i), (iii) & (iv) D. (ii), (iii) & (iv) E. (iii), (iv) & (v) 38. Which ONE of the following pairs has the member with the greater molar entropy listed first? A. HCl(l), HCl(g) B. Mg(s), Sr(s) C. CH 3 OH(l), C 2 H 5 OH(l) D. O 3 (g), O 2 (g) E. BaO(s), Ba(OH) 2 (s) 39. Component of air Mole Fraction nitrogen oxygen argon What is the partial pressure of oxygen (in mm Hg) in the atmosphere when the atmospheric pressure is 770 mm Hg? A. 161 B. 159 C D. 601 E Consider the following reaction. 4Fe (s) + 3O 2 (g) 2Fe 2 O 3 (s) Predict the change in entropy (ΔS sys ) for the above reaction: A. approximately zero B. negative C. positive D. There s not enough information to make an estimate. E. It depends on ΔH sys.

13 Chem 102, Final Exam, April 2014 Page 13 of For all of the following reactions both G and H are negative. For which reactions is G more negative than H? (You do not need thermochemical data to answer this question.) (i) N 2 F 4 (g) 2 NF 2 (g) (ii) H 2 (g) + ½O 2 (g) H 2 O(g) (iii) 2PbS(s) + 3O 2 (g) 2 PbO(s) + 2 SO 2 (g) A. i B. ii C. iii D. i & iii E. ii & iii 42. A certain chemical reaction at 25 C has ΔH = 19.5 kj mol -1 and ΔS = 42.7 J K 1 mol -1. Which one of the following statements about this reaction is TRUE? (Assume that ΔH and ΔS do not change much with temperature.) A. The reaction leads to an increase in the entropy of the system. B. ΔG at 298 K is positive. C. The reaction is not spontaneous at standard conditions and 25 C. D. There is a temperature above which the reaction becomes non-spontaneous. E. The rate constant for this reaction depends on ΔH rxn. 43. The value of ΔG for the following reaction is kj. Use this value and the information on the Data Sheet to calculate the standard free energy of formation, ΔG f, of CO 2 (g) in kj mol C 4 H 10 (g) + O2 (g) 4CO 2 (g) + 5 H 2 O(l) 2 A B. 333 C D. 394 E For a reaction with a positive G value, which of the following statements is/are FALSE? i. The equilibrium constant K is less than one. ii. The reaction is non-spontaneous when all the reactants and products are in their standard states. iii. The entropy change for the universe is negative. iv. The reaction is always endothermic. A. I B. ii C. iii D. iv E. i & ii

14 Chem 102, Final Exam, April 2014 Page 14 of The standard free energy change ( G ) for the reaction of ammonia with water is kj mol -1 at 25 C. NH 3 (aq) + H 2 O(l) NH 4 + (aq) + OH - (aq) What is the value of G ( in kj mol -1 ) when the concentrations of NH 3 (aq) = 0.10 M, NH 4 + (aq) = 1.0 x 10-3 M, and OH - (aq) = 1.0 x 10-3 M? A B C D E Rank the standard molar entropy of the following from lowest to highest: (i) SO 2 (l) (ii) SO 2 (g) (iii) SO 3 (l) (iv) SO 3 (g) A. iv < i < iii < ii B. i < iii < iv < ii C. iii < i < iv < ii D. ii < iv < iii < i E. i < iii < ii < iv 47. For the reaction: C 2 H 4 Br KI C 2 H KBr + KI 3 the initial rate data at 60 C are: [C 2 H 4 Br 2 ] (M) [KI] (M) Δ[KI 3 ]/Δt (Mmin -1 ) What is the value of the rate constant for the reaction (in L 2 mol -2 min -1 ) if the rate law is rate = k [C 2 H 4 Br 2 ][KI] 2? A B C D E

15 Chem 102, Final Exam, April 2014 Page 15 of The isomerization reaction CH 3 NC CH 3 CN is a first-order reaction. At T = ºC the rate constant k = s -1. If [CH 3 NC] initially (i.e. at time = 0) is M, then [CH 3 NC] after 1000 seconds is? A M B M C M D M E M 49. For some reaction involving carbon monoxide (CO), the plot at the right indicates A. the reaction order for CO is zero. B. the reaction order for CO is one. C. the reaction order for CO is two. D. the rate constant varies with temperature. E. the instantaneous rates at various times. 50. Which of the following statements is CORRECT? A. The reaction stops when equilibrium is reached. B. If one starts with a higher partial pressure of reactant, the equilibrium constant will be larger. C. In an equilibrium reaction, the reverse reaction will begin as soon as any products are formed. D. A chemical equilibrium is not affected by increasing the concentrations of products. E. If we make the reaction go faster, we can increase the amount of product formed at equilibrium.

16 Chem 102, Final Exam, April 2014 Page 16 of The rate law for the reaction 2 NO 2 (g) N 2 O 4 (g) is rate = k [NO 2 ] 2. Which of the following changes will quadruple the reaction rate? A. The pressure of NO 2 is halved. B. Decreasing the temperature. C. The volume of the container is doubled. D. The pressure is decreased. E. Doubling the concentration of NO 2 (g). 52. Based on the following information, which compound has the weakest intermolecular forces? Substance ΔH vap (kj/mol) Argon 6.3 Benzene 31.0 Ethanol 39.3 Water 40.8 Methane 9.2 A. Methane B. Argon C. Ethanol D. Water E. Benzene 53. The main harmful effect of the presence of large amounts of biodegradable organic matter in a lake or pond is: A. The organic matter causes the water to become murky. B. Decay of the organic matter causes the water to become depleted in dissolved oxygen. C. The organic matter blocks sunlight needed by aquatic plants. D. The organic matter causes warming of the water as it decomposes. E. The organic matter settles to the bottom, displacing bottom-dwelling species. 54. It is often necessary to remove some of the hardness of water to be used domestically because of the following problems; (i) Build-up of CaO concentrations in the water. (ii) Formation of scale deposits in kettles and water pipes. (iii) Hard water is unhealthful to drink. (iv) Hard water leads to precipitation of soap scum when washing. (v) CaCO 3 has a bad taste. A. ii and iii B. All of the above C. i and v D. i, ii, and iv E. ii and iv

17 Chem 102, Final Exam, April 2014 Page 17 of Ozone in the upper atmosphere is destroyed by the following mechanism (elementary steps): Cl(g) + O 3 (g) ClO(g) + O 2 (g) (slow) ClO(g) + O(g) Cl(g) + O 2 (g) (fast) The following statements may be deduced from the mechanism. Which one is INCORRECT? A. The overall chemical equation predicted by this mechanism is O 3 (g) + O(g) 2O 2 (g) B. ClO is an intermediate in this mechanism. C. The overall rate law is Rate = k[o 3 ] D. The activation energy of the first step is greater than the activation energy of the second step. E. The slow step is bimolecular. 56. Which of the following statements about fresh water is INCORRECT? A. Nitrogen-containing and phosphorus-containing compounds contribute to water pollution by causing excessive growth of aquatic plants, leading to eutrophication. B. Hard water has an excess of Ca 2+ ions. C. Disinfection of drinking water can be accomplished by treatment with CO 2. D. One of the drawbacks of chlorination is production of trihalomethane molecules. E. Disinfection of drinking water can be accomplished by treatment with ultraviolet light. 57. In a calibration experiment the heat capacity of a constant volume bomb calorimeter was measured to be C = 8.41 kj C 1. In a second experiment in the same calorimeter, mol of diamond (pure carbon) was burned and the temperature increased from C to C. Calculate ΔE for this combustion (in kj mol 1 ). A. 396 B C D. 369 E. 12.4

18 Chem 102, Final Exam, April 2014 Page 18 of The data in the table below were obtained for the following reaction: A + B C The rate law for this reaction is A. rate = k[a][b] B. rate = k[c] C. rate = k[a] 2 [B] D. rate = k[a] 2 E. rate = k[a] 2 [B] What are the units of the rate constant for a first order elementary reaction of the form A products? A. M s -1 B. M s C. M -1 s -1 D. M -1 s E. s For the second order reaction 2A B k = 25 L mol -1 s -1. If [A] 0 = M, how long will it take for the concentration of reactant A to reach one third of its initial value? A. 12 s B s C. 8.3 s D s E The magnitude of the rate constant is determined by which of the following factors? i. the concentrations of the reactants ii. the nature of the reactants iii. the temperature iv. the presence of a catalyst A. i & ii only B. i & iii only C. ii, iii & iv only D. i, ii, & iii only E. ii & iii only

19 Chem 102, Final Exam, April 2014 Page 19 of The reaction profile for the reaction A D is given below, which of the following statement(s) is (are) CORRECT? (i) There are 2 intermediates and 3 transition states. (ii) Step C D is the rate-determining step. (iii) The overall reaction A D is endothermic. A. (i) only B. (ii) only C. (iii) only D. (i) and (ii) E. (i) and (iii) 63. Astatine (At) is the halogen about which the least is known. This is because it is radioactive with a short half-life. The isotope 210 At has a half-life of 8.1 hours How long will it take for 20% of a given sample of At-210 to decay, assuming first-order kinetics for the decay? A h B h C h D h E. 2.6 h 64. When sodium hydrogen carbonate is heated it decomposes according to the following reaction: 2NaHCO 3 (s) Na 2 CO 3 (s) + CO 2 (g) + H 2 O(g) If sufficient baking soda is placed in a container and heated to 90ºC, the total pressure in the container is measured to be atmospheres. What is the value of K p for this reaction? (You need to assume that no other gases are present.) A B C D E

20 Chem 102, Final Exam, April 2014 Page 20 of Consider the equilibrium 4 NH 3 (g) + 5 O 2 (g) 4 NO(g) + 6 H 2 O(g). Which one of the following statements correctly describes what happens when the change is made in the reaction vessel. A. NO is added to the reaction vessel the amount of H 2 O increases B. O 2 is removed from the reaction vessel the amount of NH 3 increases C. NH 3 is added to the reaction vessel the value of K P decreases D. The total pressure is increased by compression the amount of NO increases E. The total pressure is increased by compression no change in concentrations is observed ***************************************END of EXAM ********************************