ACS Standardized Exam for CHM 122—Breakdown of Questions by Topic Question # Topic Covered Problem Set Section in ACS Book 1 – 12 (12 Q's) Kinetics 1, 2 Dynamics 13 – 24 (12 Q's) Equilibrium 3, 4, 5, 6, 7 Equilibrium 25 – 36 (12 Q's) Thermodynamics 8 Energetics 37 – 48 (12 Q's) Electrochemistry 9 Electrochemistry and Redox 49 – 56 (8 Q's) Solutions 57 – 64 (8 Q's) Organic Chemistry 65 – 72 (8 Q's) Descriptive Chemistry 73 – 80 (8 Q's) Nuclear Chemistry YOU WILL SKIP THIS SECTION ENTIRELY 12 none YOU WILL SKIP THIS SECTION ENTIRELY 10 none TOTAL Q's THAT YOU WILL ANSWER = 64 (not 80); TIME ALLOTED = 90 min. (not 110 min) 1. The addition of a catalyst to a chemical system a. b. c. d. 2. increases the concentration of products at equilibrium. increases the fraction of reactant molecules with a given kinetic energy. provides an alternate path with a different activation energy. lowers the enthalpy change in the overall reaction. 2 SO2(g) + O2(g) 2 SO3(g) The forward reaction is proceeding at a certain rate at some temperature and pressure; when the pressure is increased, we may expect for the forward reaction a. b. c. d. e. 3. a greater rate of reaction and a greater yield of SO3 at equilibrium. a greater rate of reaction and the same yield of SO3 at equilibrium. a lesser rate of reaction and a lesser yield of SO3 at equilibrium. a lesser rate of reaction and a greater yield of SO3 at equilibrium. no change in rate or yield. For the reaction between gaseous chlorine and nitric oxide: 2 NO(g) + Cl2(g) → 2 NOCl(g) doubling the concentration of chlorine doubles the rate of reaction. Doubling the concentrations of both reactants increases the rate by a factor of eight. The reaction is a. b. c. d. 4. first order in NO and first order in Cl2. first order in NO and second order in Cl2. second order in NO and second order in Cl2. second order in NO and first order in Cl2. Which factor would cause a change in the equilibrium constant, Kc for this reaction: 2 NOCl(g) a. b. c. d. 5. 2 NO(g) + Cl2(g) adding NO(g) decreasing the volume of the reaction vessel cooling the system adding an inert gas When the reversible reaction N2 + O2 2 NO has reached a state of equilibrium, a. no further reaction takes place. b. the total moles of products must equal the remaining moles of reactant. c. the addition of catalyst will cause formation of more NO. d. the concentration of each substance in the system will be constant. e. the product [N2] x [O2] equals [NO]2. 6. Given the reaction 2 X(g) + Y(g) 2 Z(g) H = 335 kJ which combination of pressure and temperature gives the highest yield of Z at equilibrium? a. b. c. d. e. 7. HCl is a strong acid. What is the pH of 200 mL of 0.002 M HCl? a. 2.0 8. d. 4.0 Hydrocyanic acid is a weaker acid than acetic acid. Hydrocyanic acid is less soluble in water than acetic acid. Cyanides are less soluble than acetates KCN ionizes to give three ions; KC2H4O2 ionizes to give eight ions. Acetic acid is a weaker acid than hydrocyanic acid. NH4Cl and NaCl NaOH and HCl NH3 and NH4Cl NaOH and NaCl NH3 and NaCl If the concentration of a saturated solution of SrCO3 is 0.000040 M, what is the value for the solubility product constant of this salt? a. b. c. d. e. 11. c. 3.4 The addition of a small amount of acid or base will have very little effect on the pH value of a solution containing equal molar concentrations of: a. b. c. d. e. 10. b. 2.7 Which is a logical inference from the fact that a 0.10 M solution of potassium acetate, KC2H3O2, is less alkaline than a 0.10 M solution of potassium cyanide, KCN. a. b. c. d. e. 9. 1000 atm and 500 °C 500 atm and 500 °C 1000 atm and 100 °C 500 atm and 100 °C catalyst, 500 atm and 100 °C 4.0 x 10-4 4.0 x 10-5 1.6 x 10-7 1.6 x 10-9 1.6 x 10-11 If two salts, AX and BX2, have the same Ksp value of 4.0 x 10-12 at a given temperature, then a. b. c. d. their molar solubilities in water are the same. the salts are more soluble in 0.1 M NaX than in water. the molar solubility of AX in water is less than that of BX2. addition of NaX will not affect the solubilities of the salts. 12. A buffer of pH 4.1 is to be prepared from a weak acid and its salt. The best acid from which to prepare the buffer is a. b. c. d. 13. The same quantity of electricity is passed through 1 M solutions of HCl and H2SO4 at different temperatures. The number of grams of hydrogen evolved from the H2SO4 solution, compared to that evolved from the HCl solution, is a. b. c. d. e. 14. phthalic acid, K1 = 1.3 x 10-3 (first ionization) hydrogen phthalate, K2 = 3.9 x 10-5 (second ionization of phthalic acid) benzoic acid, K = 6.3 x 10-5 hydrocyanic acid, K= 4 x 10-10 twice as much one half as much the same a function of the molarity of the solutions a function of the temperature of the solutions If each of these ions were reduced to metal with one coulomb, which would yield the greatest mass? a. Cu2+ (aq) b. Ag+ (aq) c. Hg2+ (aq) d. Cu+ (aq) 15. What is true in the galvanic cell in which the overall reaction is Mg(s) + Br2(l) → Mg2+(aq) + 2 Br-(aq) a. b. c. d. 16. Which of these salts is colored? a. b. c. d. 17. The Br2 | Br- electrode is the anode. Mg2+ ions migrate towards the cathode. An increase in concentration of Mg2+ would increase the cell voltage. The electrons enter the magnesium electrode from the external circuit. Al(NO3)3 Ni(NO3)3 Ba(NO3)2 Sr(NO3)3 The products of the reaction of an active metal of group IA with excess liquid water are best represented by a. b. c. d. MOH and H2 M+(aq) and OH-(aq) and H2 MOH and O2 and H2 M2O and H2 18. Which statement is true? a. b. c. d. 19. Molecular oxygen is paramagnetic Oxygen and ozone are isotopes H2SO4 is called sodium sulfite Na2SO4 is called sodium sulfite Which compound is an isomer of CH3-CH2-CH2-OH? a. b. c. CH3-CH=CH-OH CH3-O-CH2-CH3 HO-CH2-CH2-CH3 OH CH d. 20. CH2 A product of a reaction between an alcohol and a carboxylic acid is a. b. c. d. 21. H2C an aldehyde a ketone an ether an ester Which is the formula of an alcohol? a. b. CH3CH2CH2-O-CH3 CH3CH2CH2-OH O c. CH3CH2CH2-C-H O d. 22. CH3CH2-C-CH3 A radioactive atom having an atomic number of 82 and an atomic mass of 214 u loses a beta particle. The element that is the product of this nuclear change has a. b. c. d. e. atomic number mass number 80 80 81 83 82 210 212 213 214 213 23. A sample of radioactive isotope initially contains 20 x 1010 atoms. After 16 days, 5 x 1010 atoms remain. What is the half-life of the isotope? a. b. c. d. 4 days 8 days 12 days 16 days 24. The diagram to the right represents a specific mixture of S atoms and O2 molecules in a closed container. O2 molecule Circle the diagram below that shows what the container would look like after this actual mixture reaches S atom equilibrium according to the equation below: 2 S + 3 O2(g) (a) 2 SO3(g) K >> 1 (b) (c) (d) 25. If the systems in both beakers are at equilibrium, which salt has the smaller Ksp? (e) dissolved ions T = 298 K a. salt A b. salt B c. more information is needed solid salt A solid salt B 26. If Q > Ksp in the beaker with salt C, which picture best represents what the system might look like after some time passes? dissolved ions solid salt C a. ANSWERS: 1. c 9. c 17. b 25. a b. 2. 10. 18. 26. a d a a c. 3. d 11. c 19. b 4. c 12. c 20. d d. 5. d 13. c 21. b 6. a 14. b 22. d 7. b 15. b 23. b 8. a 16. b 24. d