Name: ________________________ Class: ___________________ Date: __________ Form: A1Exam 2Multiple ChoiceIdentify the choice that best completes the statement or answers the question.Record the test form letter in the TEST FORM box on your ParSCORE form.Record your name on the top of this exam and on the scantron form.Be sure to fill out your perm ID# on your scantron correctly. Record all of your answers on the scantron form. 1. (5 points) Consider three 1.0-L flasks at STP. Flask A contains Ar gas, flask B contains Kr gas, and flask C contains H2 gas.In which flask do the gas particles have the lowest average kinetic energy?a. flask Ab. flask Cc. flask Bd. The gas particles in only two of the flasks have the same average kinetic energy.e. The gas particles in ALL of the flasks have the same average kinetic energy. 2. (5 points) At 400 K, the equilibrium constant for the reaction Br2 (g) + Cl2 (g) 2 BrCl (g)is Kp = 7.0. A closed vessel at 400 K is charged with 1.00 atm of Br2 (g), 1.00 atm of Cl2 (g), and 2.00 atm of BrCl (g). a. The equilibrium partial pressures of Br2, Cl2, and BrCl will be the same as the initial values.b. The equilibrium partial pressure of BrCl (g) will be greater than 2.00 atm. c. The reaction will go to completion since there are equal amounts of Br2 and Cl2.d. At equilibrium, the total pressure in the vessel will be less than the initial total pressure.e. The equilibrium partial pressure of Br2 will be greater than 1.00 atm.Name: ________________________ Form: A2 3. (4 points) The conjugate base of H2PO4– is ________.a. HPO42–b. PO43–c. H2PO4d. H3PO4e. none of the above 4. (5 points) A solution in which [OH–] = 10–8 M has a pH of ___ and is ___.a. 8, basicb. 8, acidicc. 6, basicd. –8, basice. 6, acidicWhich is true for a system at equilibrium? 5. (2 points) Forward and reverse reactions continue to occura. TRUE b. FALSE 6. (2 points) The state can ONLY be achieved if initially there were no productsa. TRUE b. FALSE 7. (2 points) Concentration of reactants and the concentration of products are equala. TRUE b. FALSEName: ________________________ Form: A3 8. (5 points) The value of K for the following reaction is 0.16: A (g) + B (g) C (g) + D (g) The value of K at the same temperature for the reaction below is ________. 3C (g) + 3D (g) 3A (g) + 3B (g)a. 2.4 × 102 b. 6.3 c. 4.1 × 10–3d. 2.1 e. 5.3 × 10–2 9. (5 points) When the temperature of an endothermic equilibrium is increased, which of the following will happen?a. Equilibrium will shift left and the K will increase.b. Equilibrium will shift left and the K will decrease. c. Equilibrium will shift right and the K will increase.d. Equilibrium will shift right and the K will decrease. e. No shift will happen, K will stay constant 10. (5 points) Given that a sample of air is made up of nitrogen, oxygen, and argon in the mole fraction of 0.78 N2, 0.21 O2 and 0.01 Ar, what is the density of air at 1 atm and 0 oC?a. 4.5 g/Lb. 29 g/Lc. 1.3 g/Ld. 15 g/Le. 0.013 g/LName: ________________________ Form: A4 11. (5 points) A sample of solid NH4NO3 was placed in an evacuated container and then heated so that it decomposed explosively according to the following reaction: NH4NO3(s) N2O(g) + 2H2O(g)At equilibrium, the total pressure in the container was found to be 1.93 atm at a temperature of 500°C. Calculate KP.a. 1.93b. 3.72c. 28.8d. 1.07e. 1.66 12. (5 points) For the reaction below:HNO3 + HSO3– NO3– + H2SO3a. K = 1b. K > 1c. K < 1d. Cannot be determined 13. (4 points) A sample of oxygen gas (O2) was found to effuse at a rate equal to three times that of an unknown gas. The molecular weight of the unknown gas is ________ g/mol.a. 10.7b. 288c. 55d. 96e. 4Name: ________________________ Form: A5 14. (5 points) In which of the following aqueous solutions does the weak acid exhibit the highest percentage dissociation?a. 0.01 M HClO b. 0.01 M HCN c. 0.01 M H2CO3 d. 0.01 M CH3COOHe. 0.01 M H2SO3 15. (5 points) Consider the following reaction at equilibrium: 2 NH3 (g) N2 (g) + 3 H2 (g)The moles of H2 in the reaction container will increase with ________.I) some removal of NH3 from the reaction vessel (V and T constant)II) a decrease in the total pressure (T constant)III) an increase in total pressure by the addition of helium gas (V and T constant)a. I onlyb. II onlyc. III onlyd. more than one one thesee. none of these 16. (5 points) Under which conditions of temperature and pressure would helium behave most like an ideal gas?a. 50 K and 0.20 atmb. 50 K and 6.0 atmc. 750 K and 0.20 atmd. 750 K and 6.0 atme. STPName: ________________________ Form: A6 17. (4 points) Which of the following is true for the van der Waals equation for real gasesI. gas particles have non-zero volumes and interact with each other.II. the non-zero volumes of gas particles effectively decrease the amount of "empty space" between them.III. the molecular attractions between particles of gas increases the pressure exerted by the gas.a. Ib. I & IIc. I & IIId. II & IIIe. I, II & III 18. (4 points) Zinc reacts with aqueous sulfuric acid to form hydrogen gas:Zn (s) + H2SO4 (aq)  Zn SO4 (aq) + H2 (g)In an experiment, 201 mL of wet H2 is collected over water at 27 °C and a barometric pressure of 765 torr. How many grams of Zn have been consumed? The vapor pressure of water at 27 °C is 26.74 torr. a. 519b. 0.519c. 4.38 × 106d. 3.94 × 105e. 0.537 19. (5 points) For which one of the following reactions is KC equal to KP?a. 2 SO3(g) 2 SO2(g) + O2(g)b. C(s) + CO2(g) 2 CO(g)c. H2(g) + Cl2(g) 2 HCl(g)d. N2O4(g) 2 NO2(g)e. 4 Fe (s) + 3 O2 (g) 2 Fe2O3 (s)Name: ________________________ Form: A7 20. (6 points) The pH of a 0.55 M aqueous solution of a weak acid, HA, at 25.0 °C is 4.48. What is the value of Ka for HA?a. 6.0 × 10–5 b. 3.3 × 10–5c. 1.1 × 10–9 d. 2.0 × 10–9e. 3.0 × 104 21. (6 points) In the coal-gasification process, carbon monoxide is converted to carbon dioxide via the following reaction: CO (g) + H2O (g) CO2 (g) + H2 (g)In an experiment, 0.35 mol of CO and 0.40 mol of H2O were placed in a 1.00-L reaction vessel. At equilibrium, there were 0.22 mol of CO remaining. KC at the temperature of the experiment is ________.a. 0.28b. 1.0c. 3.5d. 5.5e. 0.75Name: ________________________ Form: A8 22. (6 points) Determine the initial ammonia concentration, NH3(aq), that results in an aqueous solution