2.1) Name the following 4 compounds: [1 point each, 4 total] 2.2) Draw the following compounds in the box provided [1 point each, 4 total]

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1 The exam will be composed of 3 sections. The first section will contain ~30 multiple choice marked at 1 point each. The second section will consist of ~6 questions of ~4 points each for ~24 points. The third section will consist of ~ 8 questions of ~ 6 points each. Section 1: Multiple Choice: (20 marks total) No samples provided, see quizzes and midterms for examples. Section 2: Short Answer (25 marks total) 2.1) Name the following 4 compounds: [1 point each, 4 total] CH 3 CH 3 1,2-dimethylbenzene CH 3 H 2 C F F 3,3-difluorobut-1-ene 2.2) Draw the following compounds in the box provided [1 point each, 4 total] a) 3-methylcyclopentanone Page 1 of 9

2 b) 3-methylcyclopentanone c) 2,3-dimethylbutanoic acid d) N-tert-butylcyclohexanamine 2.3a) Indicate which of the following would be the stronger acid and justify your answer! [2 Marks] 2-methylpropanoic acid compared to 3,3-dichloro-2-methylpropanoic acid Page 2 of 9

3 2.3b) Indicate which of the following would be the stronger base and justify your answer! [2 Marks] 1,1-dichloro-2-methylpropan-2-amine compared to 2-methylpropan-2-amine 2.4) For the compounds below indicate How many 1º, 2º or 3º Carbons and Hydrogens are present. Circle any Chiral centers. [5 Marks] H 3 C CH 3 H 3 C CH 3 H 2 N O O NH 2 OH 1º Carbons 1º Hydrogens 2º Carbons 2º Hydrogens 3º Carbons 3º Hydrogens 1º Carbons 1º Hydrogens 2º Carbons 2º Hydrogens 3º Carbons 3º Hydrogens 2.5) For the compounds below indicate it s conjugate acid or base and calculate the appropriate Ka or Kb for that conjugate acid or base. [4 marks] Acid or base Ka or Kb pk Conjugate Ka or Kb pk HClO x ClO 2 C 2 H 5 NH x CHO x HONH Page 3 of 9

4 2.6) The following table indicates the relative rates of a series of Nucleophilic Substitution reactions. Explain the order of the relative rates (one sentence) and then indicate if and how the order would change if the mechanism proceeded by an SN1 mechanism. [4 marks] Explaination: For a SN1 Mechanism : Page 4 of 9

5 Section 3: Long Problems (55 marks total) 3.1) If 24 g of ice at -5ºC is added to a isolated dewar containing 50 ml of water at 10ºC. what would the temperature of the system be at equilibrium if the heat capacity can be ignored and the system is completely isolated. [6 marks] 3.2) If g of ethyl ketone (C 4 H 8 O) is completely combusted in a bomb calorimeter assembly with a heat capacity of kj/ºc and an initial temperature of 22 ºC, what is the final temperature? [2 marks] (ΔH combustion = kj/mol) Page 5 of 9

6 3.3) Consider the following reaction mechanism: What effect will the following have on the rate? [6 marks] a. addition of Br- b. using a stronger nucleophile c. using a more concentrated nucleophile 3.4) Starting with the given Newman Projection and rotating the front carbon clockwise, predict (and draw!) the separate Newman Projections and the energy profile diagram for the molecule shown: [ 5 marks] Br H H H Br H Potential Energy Page 6 of 9

7 3.5a) The decomposition of AB 3 is first order with a k = 1.5 x 10-5 s -1 at 25ºC. If the initial concentration of AB 3 is M, what is the concentration after 2 min? [3 marks] 3.5b) What is the half-life for the reaction above? [2 marks] 3.6a) Calculate how much Formic acid (HCHO 2 )(Ka = 1.8 x 10-4 ) and it s sodium salt to add to 500 ml volumetric flask in order to make a buffer of ph 4.75 [3 marks] 3.6b) If 10 ml of 0.01 M NaOH is added to 20 ml of the solution created in 3.6a, determine the ph and the concentration of Na +. [2 marks] Page 7 of 9

8 3.7) Determine a) the order of each reactant, b) the order of the reaction, c) write the rate law and d) calculate the rate constant, k, for the following data: [5marks] Reaction [A] [B] rate M 0.10 M 3.50 x x x 10-3 Order of A Order of B. Reaction Order Rate Law. k =. 3.8a) Determine the ΔHº for reaction #1 given the information provided; [3 marks] Reaction 1) C 2 H 4 (g) + Cl 2 (g) C 2 H 4 Cl 2 (l) Reaction 2) 4HCl (g) + 2Cl 2 + 2H 2 O (l) ΔHº = ΔHº = kj Reaction 3) 2HCl + C 2 H 4 (g) + ½ O 2 (g) C 2 H 4 Cl 2 (l) + H 2 O (l) ΔHº = kj 3.8b) If Δ f Hº of C 2 H 4 (g) is kj /mol, what is Δ f Hº for C 2 H 4 Cl 2 (l)? [2 marks] Page 8 of 9

9 3.9) Consider the reaction; 2 SO 2 (g) + O 2 (g) 2 SO 3 (g) Kp = 600ºC If at some point the partial pressure of the gases SO 2, O 2 and SO 3 are measured as atm, 1.65 atm and 5.62 atm. Is the system at equilibrium? If not what direction would it be moving? Justify your answer by calculating ΔG. [6 marks] Page 9 of 9