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: (30 marks total) No samples provided, see quizzes and midterms for examples. Section 2: Short Answer (28 marks total) 2.1) Name the following 4 compounds: [1 point each, 4 total] C 3 C 3 C 3 N Br F C 3 2.2) Draw the following compounds in the box provided [1 point each, 4 total] a) para-dichlorobenzene Page 1 of 10

2 b) hexane-2,3-dione c) but-1-en-3-yne d) (1E)-1-chloro-2-methylbut-1-ene 2.3a) Indicate which of the following would react faster with via a SN1 reaction and justify your answer! [2 Marks] 2-iodo-2-methylpropane compared to 2-bromo-2-methylpropane Page 2 of 10

3 2.3b Indicate which of the following would react faster with C 3 via a SN2 reaction and justify your answer! [2 Marks] Br C 3 compared to Br C 3 3 C C 3 2.4) Consider Electrophilic addition of 2 to each of the the following isomers. For each indicate the most probable product. [6 Marks] Page 3 of 10

4 2 S Ka = 1.0 x C Chemistry 123: Physical and rganic Chemistry 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 K pk Conjugate N 2 N 2 Kb = 8.5 x 10-7 Kb = 4.2 x 10-4 C 3 N a) Fill in the missing values in the following table; [4 marks] Name Δ f º (kj/mol) ΔG fº (kj/mol) ΔS fº (J/mol) C3 (g) C3 (l) (C3)2C (g) C22 (g) b) Based on values in the table presented in 2.6a, how much heat would be required to vaporize 1 mole of Methanol? [2 marks] Page 4 of 10

5 Section 3: Long Problems (42 marks total) 3.1a) If 2 g of copper shot at 600ºC is added to an isolated dewar containing 100 ml of water at 20ºC. What would the temperature of the system be at equilibrium if the heat capacity of the dewar can be ignored and the system is completely isolated. (Specific heat copper is J /g ºC) [4 marks] 3.1b) If the water was at 100 ºC, how much water would be vaporized by 2 g of copper initially at 600 ºC. [2 marks] 3.1c) If 2 g of copper shot and 100 ml of water are in an isolated dewar at 10ºC. ow much energy would need to be removed in order to cool the system to -5ºC. Assume that the heat capacity of the dewar can be ignored and the system is completely isolated. (Specific heat copper is J /g ºC) [3 marks] Page 5 of 10

6 3.2) If the ΔGº for the following reaction is kj/mol, what is the p, p and concentration of the 2 C 3 at equilibrium if 10 g of 2 C 3 is added to 200 ml of water? 2 C C [6 marks] 3.3) ow many grams KC 2 would need to be added to a 500 ml solution of 2.5 M C 2 (Ka= 1.8 x 10-4 ) to make a buffer of p 3.2 [4 marks] Page 6 of 10

7 3.4a) If 0.1 g of Silver Nitrite (AgN 2 ; Ksp = 6.0 x 10-4 ) is added to 100 ml of water, what would the p and p be? Note: The Ka for N 2 is 7.2 x [4 marks] 3.4b) If 0.1 g of Silver Nitrite is added to 0.1 M solution of Na, what would the p be? ow much Silver Nitrite would dissolve? [2 marks] Page 7 of 10

8 3.5) For the hypothetical reaction A Products; Sketch the expected graph for the situations presented below: [4 marks] a) Reaction is first order b) Reaction is second order 3.5c) If the value of k can be calculated using on graphs above (ie., as the slope or the intercept) indicate which one and how. [2 marks] Page 8 of 10

9 3.6) What could be conveniently plotted to enable the calculation of the Activation Energy (Ea) and the Arrhenius constant (A). early indicate how each of these values could be determined from the plot. [4 marks] 3.7)Aspirin has the structure formula. At body temperature (37 C), Ka for aspirin equal 3 x If two aspirin tablets, each having a mass of 325 mg, are dissolved in a full stomach whose volume is 1 L and whose p is 2, what percent of the aspirin is in the form of neutral molecules? [3 marks] C 3 Page 9 of 10

10 3.8) Determine the Δº for reaction #1 given the information provided; [4 marks] Reaction 1) C 4 (g) + ½ 2 (g) C 2 (g) + 2 (g) Reaction 2) C 4 (g) (g) C 2 (g) (g) Reaction 3) C 4 (g) + C 2 (g) 2C (g) (g) Reaction 4) C 4 (g) + 2 (g) 2C (g) (g) Δº = Δº = -802 kj Δº = +247 kj Δº = +206kJ Page 10 of 10