7 - UNIVERSITY OF TORONTO FACULTY OF ARTS AND SCIENCE...

Info icon This preview shows pages 1–16. Sign up to view the full content.

View Full Document Right Arrow Icon
Image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 2
Image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 4
Image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 6
Image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 8
Image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 10
Image of page 11

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 12
Image of page 13

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 14
Image of page 15

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 16
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: UNIVERSITY OF TORONTO FACULTY OF ARTS AND SCIENCE AUGUST EXAMINATIONS 2015 CHM 139H1 Summer Name (print): Student No: Tutorial Section: DURATION: 3 HOURS TOTAL MARKS = 75 Calculators may be used but not shared. Programmable calculators may not be used. A PERIODIC TABLE and USEFUL DATA are attached to the back of the exam. WHEN YOU RECEIVE YOUR EXAM PAPER AND COMPUTER ANSWER SHEET: 1. Write your gem—e, student number and tutorial section on this page. 2. On the computer answer sheet: a) Write your last name, your given name, and signature at the front (top left corner) and at the back (top) of the sheet. b) Blacken the appropriate circles for your last name and initials. c) Write your student number along the top of the student number box and blacken the circles which correspond to your student number. YOUR ANSWERS ARE TO BE RECORDED ON THE COMPUTER ANSWER SHEET AND ON THIS PAPER BOTH OF WHICH MUST BE HANDED IN AT THE END OF THE EXAM. Part A (30 x 1.5 = 45 marks) 1. Clearly circle on the test paper the letter (a, b, c, d, or e) for the best answer you choose for each question. 2. Blacken the circle (below a, b, c. d, or e) on the computer sheet which corresponds to the answer you have chosen for each question. Make sure that only one answer is blackened. 3. Use soft pencil (No. 2 or softer). Do not use ink or ball point pen. 4. The computer sheet M be filled during the time allotted for the test. Part B (4 questions = 30 marks) Clearly and concisely showing your work is essential in order to receive full marks. AT THE END OF THE EXAM: Insert your computer answer sheet into your exam paper. Remain seated until all exam papers have been collected. MULTIPLE CHOICE QUESTIONS 1) A 1.000 kg sample of nitroglycerine, C3H5N309, explodes and releases gases with a temperature of 1985°C at 1.100 atm. What is the total volume of gas produced? 4 CaHsNaosls) 9 12 Cozlgl + 10 Hzolgl + 5 N2(3) + 02(8) A)4730L B)3525L C) 742.2 L D)5378L 2) Which of the lines on the figure below is the best representation ofthe relationship between the volume of an ideal gas and its temperature in Celsius, other factors remaining constant? 3 a (D A) Line a 5 e B) Line b g d C) Line c D) Lines e and d 0 0 Temperature (°C) 3) Which of the following compounds has the highest boiling point? A) H20 B) NH3 C) HCl D) H25 4) A 2.75-L container filled with C02 gas at 25°C and 225 kPa pressure springs a leak. When the container is re-sealed, the pressure is 185 kPa and the temperature is 10°C. How many moles of gas were lost? A) 3.39 mol B) 0.728 mol C) 0.0335 mol 0) 0.882 mol 5) A KCI solution is prepared by dissolving 20.0 g KCI in 250.0 g of water at 25°C. What is the vapor pressure ofthe solution if the vapor pressure of water at 25°C is 23.76 mm Hg? A) 22.0 mm Hg B) 24.6 mm Hg C) 23.3 mm Hg D) 22.9 mm Hg 6) Which one of the following is a formation reaction? ‘ A) C (diamond) -> C (graphite) B) 2C (graphite) + 3H2(g) + V202(g) -> C2H50H(l) C) C (graphite) + 4H (g) 9 CH4 (g) D) 6C (graphite) + 6H20 (s) 6 C5H1205(s) 7) The following reaction is endothermic. 2NHay—9Ndm+3HAm The reaction: A) will be spontaneous at low temperature B) is spontaneous at all temperatures C) is not Spontaneous at any temperature D) will be spontaneous at high temperature 8) Most chemical reactions are carried out under one of two conditions: I. in an open vessel at constant atmospheric pressure II. in a closed vessel Which is true? A) AE = w for condition land AH = w for condition II B) AH = w for condition I and AE = w for condition || C) AH = q for condition l and AE = q for condition ll D) AE = q for condition I and AH = q for condition ll 9) The enthalpy of vaporization at 298 K for diethylether (C4H100) is 26.0 kJ/mol. How much heat would be required to vaporize 1.00 L of the ether at 298 K if its density is 0.714 g/mL? A)ZSOJ B)186J C)130J D)741J 10) One of the elements A-D in the periodic table below has the electron configuration shown. Whichelementisit? Mr] E LL E E IL Ii L L L 4:,- 3d 412 A) Element A B) Element B C) Element C D) Element D 11) Two electromagnetic waves are represented below Which of the following statements is true for wave (b): A) lower amplitude and greater intensity than wave (a). B) lower amplitude and weaker intensity than wave (a). C) higher amplitude and greater intensity than wave (a). D) higher amplitude and weaker intensity than wave (a). 12) What is the oxidation number change for the iron in the following reaction? 2 Fe203(s) + 3 C(5) —> 4 Fe(s) + 3 C02(g) A) —3t00 B) - Etc —3 C) +3 toO D) +6to +3 13) Which one is the oxidation half reaction in the following chemical reaction? Cr2072'(aq) + 6 Cl'(aq) + 14 H+(aq) —+ 2 Cr3+(aq) + 3 C|2(aq) + 7 H20(l) A) 2 Cl'(aq) —> Cl2(aq) + 2e' B) Cr2072‘ (aq) + 14 H+(aq) ——> 2 Cr3+(aq) + 7 H20(l) + 6e‘ C) Cr2072' (aq) + 14 H*(aq) + 6e' —» 2 Cr3*(aq) + 7 H200) D) Cl2(aq) + 2e' —> 2 C|‘(aq) 14) From the diagram at the right, determine if the solid phase of this substance A) is more dense than the liquid phase. B) is less dense than the liquid phase. C) is less dense than water. P D) has the same density as the liquid phase. 1mm 0.5 aim 50 150 250 T, “0-) 15) For a reaction with rate law, Rate = k[A][B]2, what will happen to the rate of the reaction if the concentration of B is increased by a factor of 2.00? The rate will: A) Decrease by a factor of 1/2.00. 8) Increase by a factor of 4.00. C) increase by a factor of 2.00. D) Decrease by a factor of 1/4.00. 16) Given the plot below, what is the half-life of compound A? A) 6.57 seconds slope = - 0.562 5'1 B) 1.78 seconds C) 1.23 seconds D) 8.12 seconds in [A] t (seconds) 350 17) For a particular first-order reaction, it takes 48 minutes for the concentration of the reactant to decrease to 25% of its initial value. What is the value of the rate constant for the reaction? A) 2.9 x 10'2 5'1 B) 6.0 x 10'3 s;1 C) 1.0 x 104 s'1 D) 4.8 x 10'4 5‘1 18) What is W in Boltzmann's formula, 5 = k In W? A) The work times Avogadro's number B) A number expressing randomness depending of the temperature C) A fraction indicating the probability of obtaining a particular macro state 0) The number of microstates corresponding to a macro state 19) The decomposition of ozone, 03, in the stratosphere can occur by the following two-step mechanism: Br+03—9 BrO+02 BrO + O 9 Br + 02 Which species is a catalyst in this mechanism? A) BrO B) O C) Br D) 03 20) You have a solution of nitrous acid HNOZ, (Ka = 4.1 x 10'“) that has a pH of 2.34. If you add solid potassium nitrite (KNOZ) to this solution, what will happen? A) The pH will not change B) The pH will increase C) The pH will decrease D) The pKa will change 21) The rate constant for a particular reaction is 5.67 x 10'6 L mol’1 5‘1. What is the overall order of the reaction? A) Zero B) First C) Second D) Third 22) Which is the best acid to use in the preparation of a buffer with pH = 3.3? A) HOl (Ka = 2.0 x 10'“) B) HNo2 (Ka = 4.5 x 10") C) HNO; (strong acid) D) CCI3COOH (Ka = 2.0 x 10*) 23) The following plot shows two titration curves, each representing the titration of 50.00 mL of 0.100 M acid with 0.100 M NaOH. Which of the points a-d represent the half—equivalence point (the middle point) and the equivalence point, respectively, for the titration of a weak acid? A) Points 3 and b B) Points 3 and c C) Points b and d D) Points c and d 0 10.0 40.0 60.0 80.0 100.0 mL 010.100 M NaOfl added 24) The normal boiling point of hydrogen peroxide is the temperature at which the following process reaches an equilibrium: H202 vapour pressure becomes 1.0 atm: H202“) : Hzozlg) Under standard conditions, determine this equilibrium temperature (assume that AH“ and AS" are independent of temperature). A)120K H2020) H202(g) B) 418 K 0 C) 535 K AHflkJ/mol) -187.7 —136.3 D) 230 K S° (J/meol) 109.6 232.7 25) The elementary reaction between NO and H02 shown below has an activation energy of 0.80 k.l in the forward direction. Given the enthalpy change of this reaction, what is the activation energy ofthe reaction in the reverse direction? NO+H02~>N02+OH AH=-1.3 kJ A) 2.1 kJ moi1 B) 6.5 kJ mol'1 C) 0.50 kl mor1 D) 1.3 k] mor1 26) According to the diagram at the right, the forward reaction is: Gmhsfreemmforamcfionnimn 21—; A) Nonspontaneous at d, at equilibrium at e, and spontaneous at f. / B) Spontaneous at d, at equilibrium at e, and nonspontaneous at f. g b ~Q C) Spontaneous at d, e, and f. D) Nonspontaneous at d and e, and spontaneous at f. Ce T r r 1 r reactants a c f Pmch reactiorzprogess—p 27) A salt bridge is used to: A) Provide reactants for the redox reaction. B) Allow the ion flow necessary for cell neutrality. C) Determine the direction of the cell reaction. D) Control whether the cell is electrolytic or galvanic. 28) Doubling all of the stoichiometric coefficients in a redox reaction: A) Doubles E° but does not change AG". B) Does not change E° or A6“. C) Doubles AG“ but does not change E”. D) Doubles both E“ and AG". 29) Which of the following statements concerning the rusting of iron is false? A) Dissolved salt increases the rate of corrosion by providing ions to carry the current. B) The oxidation site can occur at a different place on the metal surface away from the reduction site. C) In rusting, iron is reduced. D) The rusting of iron requires both oxygen and water. 30) Shown at the right is an electrochemical cell with anode a and cathode c. Both the anode and the cathode are inert electrodes. The liquid shown in compartment b of the cell is molten potassium chloride, KCl. Determine which cell description below is true: A) This is a Galvanic cell with Anode reaction: 2K(l) —> 2K*(/) +2e' Cathode reaction: 2 CH!) —> C|2(g) + Ze‘ B) This is a Galvanic cell with Anode reaction: 2 Ci'(l) —+ Cl2(g) + Ze‘ Cathode reaction: K“(/) + 2e' 9 2K(l) C) This is an Electrolytic cell Anode reaction: K(l) —> K+(l) + 2e' Cathode reaction: Cl2(g) + 2e- —+ 2 CW) D) This is an Electrolytic cell Anode reaction: 2 CW) —> Ci2(g) + 2e' Cathode reaction: K”(/) + 2e' 9 KO) ‘ (b) What is the total pressure[Ofthesystematequififii'ium‘lL ' Student Number: Tutorial: 1. (9 marks) Hydrogen pgmxidiemodqq» feasts withsoppermeta!(cuisifiogpmduce cépber = ' ions (cu’*(aq)) [and,h¥§f‘/Xl€1¢5§nslififliioqnzri “ ' ' r r (a); The rate constant‘f th v I w I, > iséty:2s.obciand5.75 hirijis‘1 7"at50.0‘°C. Whafis’ e; d‘ii'ection? , (b) What is the rate constant for this reaction in the forward directions; °C? (c) To push the reaction to thg'right to inorease the equilibrium Concentration of aqueous coppér ibns 9 _ , (Cuz‘), should the reaction be oafried out inian acidic or a basic‘huff‘er? Explain your answer. 2. (5 marks) The rearrangement :éagtion, of Houoig)jm H3049) (agnom a 1H~oz(g)) has a Kp value of0.47. ' ,' , ' ' ' . r (a) 0.89 atm of HONO added ‘ ‘ 'uiat hepa'rtiai pressure of HNOz after" the system is allowedrtoges ~; v 10., ' 3. (7 marks) The reaction betwaejnisggdium‘ ' ’ ' ' coffee cup calorimeter. _ mixed. After mixing the maximum;,_tem "r3 questions, assuming the cup and flie‘fthermame of exactly 1.0 g/mL. ' ' ' ‘ ‘ y " ' lfguricv-iacid (H2504) was studied in a . fiflgsageach at 240°C, were ‘ 30,5?9Answer the following abfsorhnol‘hmtandithat all solutions have a density 2NaoH(aq) ,+ H;SO4(aq) —> Na2504(aq) + 2H20(I) (3) Calculate the heat exchanged during this reaction. (b) Calculate the enthalpy of the reaction AH, ln kl/mOl of NazSO4 produced. 11 (b) What is AG“ for this reaction? (c) What is the equilibrium constant far this reaction? (d) What is Emu if the ions that participate in the reactiofi at thék’ck’ra’thede are present at 10 M concentration, and ions thatparticipate in the reawbn Kat‘the anode'are present at 0.001 M? 12._ PHYSICAL AND CHEMICAL CONSTANTS Atomic mass unit Mass of an electron Mass of a neutron Mass of a proton Avogadro’s number Boltzmann's constant Faraday’s constant Fundamental unit charge Gas constant Heat capacity of water Planck’s constant Rydberg's constant Speed of light Zero point Kw of H20 at 25°C Pi CONVERSION FACTORS 2.54 cm = 1 inch 1 N = 1 kg m 5'2 1 kg = 2.205 pounds (lbs) 1 nm = 10'9 m 1 A = 10‘10 m 1 Watt = 1 Joule sec'1 1 Amp 2 1 C/s 1 atmosphere (atm) = 1.01325 x 105 Pa (N m'z) = 760.0 mm Hg (torr) = 1.01325 bar 1 a.m.u. = 1.6605402 x 10'27 kg me = 9.109 x 10‘31 kg mn = 1.674 x 10'27 kg mp = 1.672 x 10‘27 kg NA = 6.0221367 x 1023 mole'1 kB = 1.380658 x 10231 K'1 F = 9.6485309 x 1040 mole'1 e = 1.60217733 x 10'19c R = 8.314510] mole'1 K'1= 0.082058 L atm mole'1 K‘1 s = 4.1841 g'1 K1 = 75.41 mole‘1 K"1 h = 6.6260755 x 10341 s RH = 2.1798 x 10131 = 1.097 x 10‘2 nm‘1 c = 2.99792458 x 108 m 5‘1 0°c = 273.15 K Kw = 1.00 x 10'14 n = 3.1415927 1 calorie (cal) = 4.184 joules (J) 1 debye (0) = 3.335617 x 103°C m 1 eV/particle = 96.485 kJ mole'1 = 23.061 kcal mole'1 1 eV = 1.602 x 10191 = 8067 cm‘1 1 kcal mole'1 = 4.184 kJ mole'1= 349.73 cm'1 1 kJ mole"1 = 0.23901 kcal mole'1= 83.591 cm'1 1 L atm = 101.325 J = 24.217 cal ln x = 2.3026 log x 13 USEFUL EQUATIONS E=hv A=c/v 7t=h/mv Ephomn=hvo + Ek En = - RHZz/n2 PV=nRT (P+n2a/V2)(V-nb)=nRT KE = V2 mu2=3RT/(2NA) urms = (3RT/M)1/2 An, = Kbm An: Kfm n=MRT —bi-«/b2 —4ac 2a Psolution=XsoiventPso|vent ax2+bx+c=0 x= |n(ab)= |n(a)+ ln(b) ; k Kp=Kc(RT)A"; An = c + a‘ - {a +b) Arrhenius equation: k = Ae‘ea/RT 1n[k_z]=(' First order reaction: |n{[A]o/[A]} = kt t1/2= 0.693/k Second order reaction: 1/[A] — 1/[A]o = kt t1/2=1/k[A]o Zero order reaction: [A]: -kt + [A10 pH = -|og[H30+] pOH = -|og[OH'] pH + pOH = 14 Kax Kb = Kw q=nCAT w=—PAV AE=q+w AH=AE+PAV A5univ = A$+A$5urr T AH” = ZcoefprH; (pdts) — ZcoeffrAH; (rcts) A5” = Zcoeffp5°(pdts) — Zcoeffi5°(rcts) AG ° = ZcoefprGf (pdts) — Z coej‘fr AG; (rcts) A6 = AH —TAS AG=AG° +RT|nQ AG°=—RT1nK RT E=E°———|nQ [=P£ AG=—nFE “F t . Zeroth order M/s or M 5‘1 pH = PK“ + log [Eonjugate base] Us or 5‘1 [acid] 1/(M s) or M‘1 s'1 1/(M2 s) or M'2 5'1 First order Second order Third order mexts) ‘=’ mM"*(aq) + xX"(aq) Ksp = [Mmlm [XV‘F E R ln(a/b) = -ln(b/a) ii 1 1 T2 T] J 14 Standard Reduction Potentials (in Volts), 25°C Reaction E°(V) Clz + 2e" 20' +1.36 02 + 4H“ + 4e' -) ZHZO +1.23 Brz + 2e' 9 ZBr' +1.07 Fe“ + e‘ ---> Fe“ +0-77 Ag+ + e' —--> Ag +0.80 + 2e' ---> Zl' +0.54 ~— Cu+ + e'_ -——> Cu +0.52 Fe(CN)63‘ + e' ---> Fe(CN)54' +0.36 Cu2+ + 2e" ---> Cu +0.34 Cu2+ + e' ---> Cu+ +0.15 5n4+ + 2e' ---> Sn2+ +0.15 2H+ + 2e' ---> H; Fe3+ + 3e' --—> Fe '0-04 Pb2+ + 2e' ---> Pb 013 Ni2+ + 2e' ———> Ni -0.26 Fe2+ + 2e' ---> Fe —O.41 w + Cr + 3e' ---> Cr -0.74 an" + 2e' ---> Zn -O.76 ZHZO + 2e' ---> H2(g) + ZOH‘ -0.83 v2+ + 2e’ ---> v -1.18 Mn2+ + Ze' -——> Mn -1.18 AI3+ + 3e" ---> Al -1.66 Mg2+ + 2e' -——> Mg -2.37 22%;... 2225< Agéfimcgazn-V 56.; 1.3 .3ng SH. 94¢ 5 .333». 3. SN HQ @0an ca .58 ma 323:2:51 :5 935.8 “En .823153 23.3. 3.58... 533235 a 22 an MD-Z—FO< 5 van in .59 BEE:- 53 35...?»sz 4:281 2: .n 2.53. 33139.2 05 .3 i=5: flue 2: «33%... net-h S nouaucu 25> 05 .maufiac 0385 0: gm: «22:0? 8.... £959.. Ems—Eu." W92 5.: 565 n 8n:— 3250 Q's-Em :85 23% .q .a: .2 :55 .12 2E S EEIOE EEQKODfimm 35—623 fig arm QB a: :3. e: 3va 9: EN. 5: Eu E: A88 2: ava m3 :3 3: 87mm 8%. 5 m0 5.an mm 83 ca 8;. $68 ea 2299i zozmx $5.02. 22230 mw>n=m 23.2.35. 3 an E 5 3.. E 5“ am mwénr Vm om.ch mm 3.3... av 5.5— 5% wine. we. 5&2. mv noéov 3. 8% n... 3.3 N1 womdm 5. 33.5 a. $3.3 an «95 an gamma FM 29.1», mzioxn uz_N «wan—00 meQz 5(80 zom— wwmz<02<2 55.20va 23_Q<z<> SEEMS-bu Q. :N 5 E 5 on .6 > M 3.3 wade en memdw aN nmwdm wN nmmdm EN 39mm 9N 3me ma “5me vu Nvmdm nu 5a.: NH $3.3. nu whodv an wmodn as m. = a 222:1: mm nofiwu Na >130mm2 mm «3: av gm «0 mm 33» mm muhmo fin 2092 szoiu 22253.2 3 a m=> h m5 u m> Q: n 2232652 3:58 Fl 25 L w a .3. _U _< 2 Z n mama S 8%" 5 main 3 «5.9:. E $8.3 S «3% 2 Bag 2 and“ 5 20m: mama-.3“. 2mw>x0 zwwomtz 20mg 205m . 23.4;1mm 02 m o z D m 3 m3 220.? mg :92 m «32:2 220.? GM! N 83“ 3 3a.? a 2.3.2 a 89.: b :3? e :3: m \S: 2/ ~53 v 22m: $5 5 <5 3 <> 2 <2 E <5 2 asfimbafifiio o zopézummeEE s. N 2329.. a mummzazmaoxo 35232305 3 um i _ m EubmmotwhwgaEmmfiigfinfi mBo._. n G ._ whszmfim ME. "—0 m._m<._. oEOEmE ...
View Full Document

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern