General Chemistry II (CHM 2046) Dr. Lufaso Print Name Practice Final Exam Fall 2014 /000 pts

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1 General Chemistry II (CHM 06) Dr. Lufaso Print Name Practice Final Exam Fall 01 /000 pts Hints and tips for studying for the final exam: There are more questions on this practice exam than the real final exam The actual final exam is not all multiple choice Study for the final before taking this practice exam o Work problems on previous exams o Work a problem from each subsection at the end of each chapter o Study notes taking during lecture Take this practice exam without a classmate, your notes, and textbook Answer key to practice exam (answers only) will be posted on Sunday evening Note: There will be questions on the final exam about topics that are not on this practice exam. Do not use this practice exam as your only study aid! 1) Which one of the following should have the lowest boiling point? A) PH B) HS C) HCl D) SiH E) HO ) Of the following, has the highest boiling point. A) N B) Br C) H D) Cl E) O ) The heat of fusion of water is 6.01 kj/mol. The heat capacity of liquid water is 75. J/mol K. The conversion of 50.0 g of ice at 0.00 C to liquid water at.0 C requires kj of heat. A).8 10 B) 1. C) 17. D) 0.69 E) Insufficient data are given.

2 ) The heating curve shown 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) AB B) BC C) CD D) DE E) EF 5) The heating curve shown 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 solid. A) AB B) BC C) CD D) DE E) EF 6) What fraction of the volume of each corner atom is actually within the volume of a face-centered cubic unit cell? A) 1 B) 1 C) 1 D) 1 8 E) 1 16

3 7) CsCl crystallizes in a unit cell that contains the Cs+ ion at the center of a cube that has a Cl- at each corner. Each unit cell contains Cs + ions and Cl -, ions, respectively. A) 1 and 8 B) and 1 C) 1 and 1 D) and E) and 8) A solid has a very high melting point, great hardness, and poor electrical conduction. This is a(n) solid. A) ionic B) molecular C) metallic D) covalent network E) metallic and covalent network 9) The solubility of oxygen gas in water at 5 C and 1.0 atm pressure of oxygen is 0.01 g/l. The solubility of oxygen in water at.0 atm and 5 C is g/l. A) 0.01 B) 0.01 C) 0.1 D) 0.1 E).0 10) The solubility of Ar in water at 5 C is M when the pressure of the Ar above the solution is 1.0 atm. The solubility of Ar at a pressure of.5 atm is M. A) B) C).0 10 D) E) ) A solution is prepared by dissolving.7 g of CaCl in 75 g of water. The density of the resulting solution is 1.05 g/ml. The concentration of CaCl is % by mass. A) 5.9 B) 6. C) 0.06 D) E) 6.

4 1) The concentration of urea in a solution prepared by dissolving 16 g of urea in 9 g of H O is % by mass. The molar mass of urea is 60.0 g/mol. A) 9 B) 1 C) 0.9 D) 0.1 E) 0.8 1) The concentration of KBr in a solution prepared by dissolving.1 g of KBr in 897 g of water is molal. A).6 B) C) D) E) ) A solution is prepared by dissolving 15.0 g of NH in 50.0 g of water. The density of the resulting solution is 0.97 g/ml. The mole fraction of NH in the solution is. A) B) C) 0.90 D) 0.9 E) ) What is the molarity of sodium chloride in solution that is 1.0% by mass sodium chloride and that has a density of 1.10 g/ml? A) 1 B).5 C).56 D). E) ) The reaction below is first order in[ho ]: HO (l) HO(l) + O (g) A solution originally at M HO is found to be M after 5 min. The half-life for this reaction is min. A) 6.8 B) 18 C) 1 D) 8 E) 5

5 The data in the table below were obtained for the reaction: A + B P 17) The rate law for this reaction is rate =. A) k[a][b] B) k[p] C) k[ A] [ B ] D) k[ A] [ B ] E) k[ A ] 18) The reaction is a first-order reaction. At 0. C, CH N C CH C N k s [CH N C] is after s A) B). 10 C) D).7 10 E) The reaction A 1 = If [CH N C] is B is first order in [A]. Consider the following data initially, 19) The rate constant for this reaction is s 1. A) B).0 10 C) 1 D) 0.6 E).0 10

6 0) The concentration of A is M after 0.0 s. A) B) 1. C) 0.17 D).5 10 E) ) The value of K eq for the equilibrium H (g) + I (g) ˆ ˆ ˆ HI (g) is 79 at 5 C. What is the value of K eq for the equilibrium below? A) 97 B) 0.05 C) 8 D) 1588 E) / H (g) + 1/ I (g) ˆ ˆ ˆ HI (g) ) Consider the following chemical reaction: H (g) + I (g) ˆ ˆ ˆ HI (g) At equilibrium in a particular experiment, the concentrations of H, I, and HI were 0.15M 0.0M and 0.55M respectively. The value of K eq for this reaction is. A) B) 111 C) D) 6.1 E) 61 ) At elevated temperatures, molecular hydrogen and molecular bromine react to partially form hydrogen bromide: H (g) + Br (g) ˆ ˆ ˆ HBr (g) A mixture of 0.68 mol of H and 0.0 mol of Br is combined in a reaction vessel with a volume of.00 L. At equilibrium at 700 K, there are mol of H present. At equilibrium, there are mol of Br present in the reaction vessel. A) B) 0.0 C) D) 0. E) 0.

7 ) An aqueous solution contains M NaOH at 5.0 C. The ph of the solution is. A) B) 1.00 C) 1.00 D) 7.00 E) ) The ph of a 0.55 M aqueous solution of hypobromous acid, HBrO, at 5.0 C is.8. What is the value of K a for HBrO? A) B) C) D) E) ) The ph of a 0.10 M solution of a weak base is 9.8. What is the K for this base? b A).1 10 B) C) D) E) ) The K a for HCN is What is the value of K for CN? b A) B) C).9 10 D) E) ) The molar concentration of hydroxide ion in pure water at 5 C is. A) 1.00 B) 0.00 C) D) E) 7.00

8 9) Of the following acids, is not a strong acid. A) HNO B) H SO C) HNO D) HClO E) HCl 0) Which one of the following is the weakest acid? HF (K = ) A) a 8 B) HClO (K =.0 10 ) a C) HNO (K =.5 10 ) a 10 D) HCN (K =.9 10 ) a 5 E) Acetic acid ( K = ) a 1) Using the data in the table, which of the conjugate acids below is the weakest acid? A) NH + B) C5H5NH + C) HNOH + NH D) CH + E) NH + and NHCH + ) Of the following, which is the strongest acid? A) HClO B) HClO C) HClO D) HClO E) HIO

9 5 ) The ph of a solution that contains M acetic acid ( K = ) and 0.17 M sodium acetate a is. A).077 B) 5. C) D) 8.70 E) 9.9 ) The Kb of ammonia is The ph of a buffer prepared by combining 50.0 ml of 1.00 M ammonia and 50.0 ml of 1.00 M ammonium nitrate is. A).6 B) 9.5 C).7 D) 9.7 E) ) Calculate the ph of a solution prepared by dissolving 0.70 mol of formic acid (HCOH) and 0.0 mol of sodium formate (NaCOH) in water sufficient to yield 1.00 L of solution. The Ka of formic acid is A).099 B) 10.6 C).56 D).07 E) ) A 5.0 ml sample of 0.7 M HClO is titrated with a 0.7 M KOH solution. What is the [H ] (molarity) before any base is added? A) 0.9 B) C) 0.7 D) E) 0.7 7) A 5.0 ml sample of 0.7 M HClO is titrated with a 0.7 M KOH solution. The HO + concentration after the addition of 10.0 ml of KOH is M. A) 0.8 B) C) 0.7 D) E) 0.7

10 8) A 5.0 ml sample of 0.7 M HClO is titrated with a 0.7 M KOH solution. The HO + concentration after the addition of 66. ml of KOH is M. A) 0.9 B) C) 0.7 D) E) 0.7 9) A 5.0 ml sample of 0.7 M HClO is titrated with a 0.7 M KOH solution. The HO + concentration after the addition of 80.0 ml of KOH is M. A) 0.0 B) C) 0.70 D) E) 10 0) The solubility of lead (II) chloride (PbCl ) is. What is the K of PbCl sp? M A) B) C) D) E) ) Calculate the maximum concentration (in M) of silver ions (Ag ) of CO.The K of Ag sp CO is in a solution that contains 0.05 M A) B) C) D) E) ) Which one of the following pairs cannot be mixed together to form a buffer solution? A) C5H5N, C5H5NHCl (pyridine is a weak base, K b for C 5 H 5 N is 1.8 x 10-9, pyridinium chloride its conjugate weak acid) B) HCHO, NaOH (CHO = acetate) (acetic acid is a weak acid, NaOH strong base) C) KOH, HI (strong acid, strong base) D) NHCH, HCl (methyl amine is a weak base, HCl strong acid) E) NaClO, HNO (NaClO is a weak base, HNO strong acid)

11 ) Which of the following could be added to a solution of acetic acid to prepare a buffer? A) sodium hydroxide B) hydrochloric acid C) nitric acid D) more acetic acid E) None of the above can be added to an acetic acid solution to prepare a buffer. Consider the following table of K sp values. ) Which compound listed below has the greatest molar solubility in water? A) CdCO B) Cd(OH) C) AgI D) CaF E) ZnCO 5) Which compound listed below has the smallest molar solubility in water? A) ZnCO B) Cd(OH) C) CdCO D) AgI E) CaF 5) Calculate the percent ionization of formic acid (HCOH) in a solution that is 0.11 M in formic acid and M in sodium formate (NaHCO ). The K a of formic acid is A) 7.8 B) C) 11. D) E).59

12 6) The value of S for the catalytic hydrogenation of acetylene to ethene, is J/K mol. A) B) C) D) E) CH (g) + H (g) CH (g) 7) The combustion of acetylene in the presence of excess oxygen yields carbon dioxide and water: The value of A) B) +1. C) +. D) -1. E) -. CH (g) + 5O CO (g) + HO(l) S for this reaction is J/K mol.

13 8) Given the thermodynamic data in the table below, calculate the equilibrium constant (at 98 K) for the reaction: SO (g) + O (g) ˆ ˆ ˆ SO (g) A).7 10 B) 1.06 C) 1.95 D).8 10 E) More data are needed. DeltaH o = (*-95) (-*97) = -196 kj DeltaS o = (*56)-(*9 + 1*05) = -191 J/K = kj/k DeltaG o = DeltaH TdeltaS = (-196 kj) - 98K*( kj/k) DeltaG o = -19 kj = -1.9x10 5 J DeltaG = -RTlnK so lnk = -(DeltaG)/RT K = e^(-(deltag)/rt) =.x10 9) The equilibrium constant for the following reaction is at 5 C. N (g) + H (g) ˆ ˆ ˆ NH (g) The value of A) B) -. C) -5 D) -50 E) - G for this reaction is kj/mol. 50) A reaction that is spontaneous as written. A) is very rapid B) will proceed without outside intervention C) is also spontaneous in the reverse direction D) has an equilibrium position that lies far to the left E) is very slow 51) S is positive for the reaction. A) H (g) + O (g) HO(g) NO (g) N O (g) B) CO (g) CO (s) C) + D) BaF (s) Ba (aq) + F (aq) E) Hg(l) + O (g) HgO(s)

14 5) For the reaction C(s) + HO(g) CO(g) + H (g) H = 11. kj / mol and S = 1.6 J / Kmol at 98 K. At temperatures greater than C this reaction is spontaneous under standard conditions. A) 7 B) 5 C) 55 D) 710 E) 98 5) A reaction that is not spontaneous at low temperature can become spontaneous at high temperature if H is and S is. A) +, + B) -, - C) +, - D) -, + E) +, 0 5) is reduced in the following reaction: + + Cr O 7 + 6S O + 1H Cr + S O 6 + 7H O A) Cr6+ B) S + + C) H D) O E) S O 6 55) is the oxidizing agent in the reaction below. + + Cr O 7 + 6S O + 1H Cr + S O 6 + 7H O A) Cr O B) S O C) H + D) Cr + E) S O ) electrons appear in the following half-reaction when it is balanced. S O S O 6 A) 6 B) C) D) 1 E)

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16 57) The electrode at which oxidation occurs is called the. A) oxidizing agent B) cathode C) reducing agent D) anode E) voltaic cell 58) In a voltaic cell, electrons flow from the to the. A) salt bride, anode B) anode, salt bridge C) cathode, anode D) salt bridge, cathode E) anode, cathode 59) The more the value of E red, the greater the driving force for reduction. A) positive B) negative C) exothermic D) endothermic E) extensive Table 0. 60) The standard cell potential (E cell) for the voltaic cell based on the reaction below is V Sn (aq) + Fe (aq) Fe (aq) + Sn (aq) A) +0.6 B) C) +1.9 D) -0.6 E) +1.1 E o cell = E o red(cathode) E o red(anode) (+0.771V) -(+0.15 V) + = V 61) The standard cell potential (E cell) for the voltaic cell based on the reaction below is V. A) +1.9 B) C) +.5 D) E) Sn (aq) + Cr (s) cr (aq) + Sn (aq)

17 6) The standard cell potential (E cell) for the reaction below is V. The cell potential for this reaction is V when the concentration of [Cu ] = M and [Zn ] = 1.0 M + + Zn (s) + Cu (aq) Cu (s) + Zn (aq) A) 1.0 B) 1.5 C) 0.95 D) 0.80 E) 1.10 E = E 0 (0.059/) ln {[Zn + ]/[Cu + ]} E = 1.10V (0.059/) ln {[Zn + ]/[Cu + ]} E = 1.10V (0.059/) ln {1.0/1.0x10-5 } = 0.95V 6) How many minutes will it take to plate out.19 g of chromium metal from a solution of current of 5. amps in an electrolyte cell? A) 5.77 B) 6 C) 115 D) 1.9 E) 17. 6) What is the oxidation number of sulfur in the HSO ion? A) - B) +1 C) + D) + E) +6 65) By what process does thorium-0 decay to radium-6? A) gamma emission B) alpha emission C) beta emission D) electron capture E) positron emission Cr + using a 66) In balancing the nuclear reaction 8 U E + He, the identity of element E is A) Pu B) Np C) U D) Pa E) Th

18 67) This reaction is an example of. A) alpha decay B) beta decay C) positron decay D) electron capture E) gamma emission 1 Ca 1 K ) Nuclei above the belt of stability can lower their neutron-to-proton ratio by. A) beta emission B) gamma emission C) positron emission D) electron capture E) Any of the above processes will lower the neutron-to-proton ratio. 69) Bombardment of uranium-5 with a neutron generates tellurium-15, neutrons, and. A) zirconium-98. B) krypton-101. C) krypton-10. D) strontium-99. E) zirconium ) 11 I has a half-life of 8.0 days. Assuming you start with a 1.5 mg sample of 11 I, how many mg will remain after 1.0 days? A) 0.85 B) 0.68 C) 0. D) 0.0 E) ) Which one of the following is a correct representation of a beta particle? A) e B) 1 β 0 C) 0 e 1 D) 0 e 1 E) β

19 7) When two atoms of H are fused to form one atom of 1 He, the total energy evolved is.8 10 J 8 What is the total change in mass (in kg) for this reaction? (C = m s) A) B) C).5 10 D) 1.15 E) ) The mass of a proton is amu and that of a neutron is amu. What is the mass defect (in amu) of a 60 Ni 9 A) 0.59 B) 1.7 C) D) E) nucleus? (The mass of a nickel-60 nucleus is amu.) 7) The half-life of cobalt-60 is 5.0 yr. How many milligrams of a.000-mg sample remains after 6.55 years? A) 0.87 B) C).779 D) E) 1.16