课程名称︰普通化学丙 课程性质︰医学系大一必带 课程教师︰陈逸聪 开课学院：医学院 开课系所︰医学系 考试日期（年月日）︰2014/1/10 考试时限（分钟）：150 是否需发放奖励金：是 （如未明确表示，则不予发放） 试题 : - 1. When one electron is added to an oxygen molecule, a superoxide ion (O ) is 2- 2 formed. The addition of two electrons gives a peroxide ion (O ). Removal + 2 of an electron from O leads to O . 2 2 - (a) Construct the correlation diagram for O . (2%) 2 (b) Give the valence electron configuration for each of the following + - 2- species: O , O , O , O . (4%) 2 2 2 2 (c) Give the bond order of each species. (4%) (d) Predict which species are paramagnetic. (3%) (e) Predict the order of increasing bond dissociation energy among the species. (1%) - + 2. The bond dissociation energies for the species NO, CF , and CF are ordered + - as CF > NO > CF . (a) Write the electron configurations of three molcules/ions. (6%) (b) What are the bond order of these molecules/ions? (3%) (c) Use M.O. theory to explain the ordering of dissociation energies. (1%) 3. A sample of pure solid naphthalene (C H ) weighing 0.6410 g is burned 10 8 completely with oxygen to CO and H O in a constant-volume 2(g) 2 (l) calorimeter at 25℃. The amount of heat evolved is observed to be 25.79 kJ. (a) Write and balance the chemical equation for the combustion reaction. (2%) (b) Calculate the standard change in internal energy (ΔU°) for the combustion of 1.000 mol naphthalene to CO and H O . (2%) 2(g) 2 (l) (c) Calculate the standard enthalpy change (ΔH°) for the same reaction as in part (b). (2%) (d) Calculate the standard enthalpy of formation per mole of naphthalene, using data for the standard enthalpies of formation of CO and 2(g) H O from reference. (2%) 2 (l) 4. If 54.0 g argon at 400K is compressed isothermally and reversibly from a pressure of 1.50 to 4.00 atm, calculate the work done on the gas and the heat absorbed by gas in the process. What are the changes in energy (ΔU) and in enthalpy (ΔH) of the gas? (Ar = 39.9) (10%) 5. Suppose 2.00 mol of an ideal gas is contained in a heat-insulated cylinder with a moveable frictionless piston. Initially, the gas is at 1.00 atm and 0℃. The gas is compressed reversibly and adiabatically to 2.00 atm. The -1 -1 molar heat capacity at constant pressure, C , equals 29.3 J K mol . P Calculate the final temperature of the gas, the change in its internal energy, ΔU, and the work done on the gas. (10%) 6. Solid tin exists in two forms: white and gray. For the transformation Sn → Sn (s, white) (s, gray) -1 The enthalpy change is -2.1 kJ and the entropy change is -7.4 J K . (a) Calculate the Gibbs free energy change for the conversion of 1.00 mol white tin to gray tin at -30℃. (2%) (b) Calculate the Gibbs free energy change for the conversion of 2.50 mol white tin to gray tin at -30℃. (2%) (c) Will white tin convert spontaneously to gray tin at -30℃? (2%) (d) At what temperature are white and gray tin in equilibrium at a pressure of 1 atm? (2%) 7. The primary medium for free energy storage n living cells is adenosine triphosphate (ATP). Its formation from adenosine diphosphate (ADP) is not spontaneous: 3- 2- + 4- ADP + HPO + H → ATP + H O ΔG = +34.5 kJ (aq) 4(aq) (aq) (aq) 2 (l) Cells couple ATP production with the metabolism of glucose (a sugar): C H O + 6 O → 6 CO + 6 H O ΔG = -2872 kJ 6 12 6(aq) 2(g) 2(g) 2 (l) The reaction of 1 molecule of glucose leads to the formation of 38 molecules of ATP from ADP. Show how the coupling makes this reaction spontaneous. What fraction of the free energy released in the oxidation of glucose is stored in the ATP? (5%) 2+ 2+ 8. A Zn|Zn ║Co |Co galvanic cell is constructed in which the standard cell potential is 0.48 V. Calculate the free energy change at 25℃ per gram of zinc lost at the anode, if all concentrations remain at their standard value of 1 M throughout the process. What is the maximum electrical work done by the cell on its surroundings during this experiment? (Zn = 65.38) (7%) 9. A galvanic cell is constructed in which the overall reaction is + 2+ Pb + 2 H O → Pb + H + 2 H O (s) 3 (aq) (aq) 2(g) 2 (l) (a) Calculate E° for the whole cell. (2%) cell - (b) Chloride ions are added until PbCl precipitates at the anode and [Cl ] 2 reaches 0.15 M. The cell potential is then measured to be 0.22 V at pH 2+ = 0 and P = 1.0 atm. Calculate [Pb ] under these conditions. (3%) H 2 (c) Calculate the solubility product constant K of PbCl . (3%) sp 2 10. Enzyme working as a catalyst to react with substrate (reactant) in biochemical reactions can be summarized by the following mechanism. k 1 → E + S ← ES ...(1) k -1 k 2 ES → E + P ...(2) (a) Use the steady state approximation to derive Michaelis-Menten equation of k [E ][S] d[P] 2 T ── = ───── ...(3) (4%) dt K +[S] m (b) K in equation (3) is called Michaelis constant. Express K by the rate m m constants in equations (1) and (2). (1%) (c) Certain bacteria use the enzyme penicillinase to decompose penicillin and render it inactive. What is the maximum rate of decomposition of -7 -5 penicillin if the enzyme concentration is 6 ×10 M? (K = 5 ×10 M, k 3 -1 m 2 = 2 ×10 s ) (3%) (d) At what substrate concentration will the rate of decomposition be half that calculated in part (c)? (2%) 11. Terminology, description, and illustration (if necessary) (a) How many degrees of freedom in the motions of translation, rotation, and vibration in a benzene molecule? (3%) (b) Describe the entropy (S) defined by L. Boltzmann. (3%) (c) Describe the Nernst equation for a chemical reaction of aA + bB → cC + dD. (3%) (d) Write the half-cell reactions and overall cell reaction for a battery that you know of. (5%) (e) Derive the half-life (t ) for a first-order reaction in terms of its 1/2 rate constant. (3%) (f) Describe the rate constant defined by S. Arrhenius. (3%) Reference//我只附计算需要用到的 Standard Chemical Thermodynamics Properties ΔH°(25℃) ΔS°(25℃) ΔG°(25℃) C (25℃) f f P Substance (kJ/mol) (J/K mol) (kJ/mol) (J/K mol) ─────────────────────────────────────── H O -285.83 69.91 -237.18 75.29 2 (l) CO -393.51 213.63 -394.36 37.11 2(g) Standard Reduction Potentials at 25℃ Half-Reaction E°(volts) ─────────────────────────────────────── + - 2 H O + 2 e → H + 2 H O 0.000 exact! 3 2(g) 2 (l) 2+ - Pb + 2 e → Pb -0.1263 (s) -- 第01话 似乎在课堂上听过的样子 第02话 那真是太令人绝望了 第03话 已经没什麽好期望了 第04话 被当、21都是存在的 第05话 怎麽可能会all pass 第06话 这考卷绝对有问题啊 第07话 你能面对真正的分数吗 第08话 我，真是个笨蛋 第09话 这样成绩，教授绝不会让我过的 第10话 再也不依靠考古题 第11话 最後留下的补考 第12话 我最爱的学分 --

※ 发信站: 批踢踢实业坊(ptt.cc) ◆ From: 140.112.196.111 ※ 编辑: xavier13540 来自: 140.112.196.111 (01/11 00:08) ※ 编辑: xavier13540 来自: 140.112.196.111 (01/11 01:44) ※ 编辑: xavier13540 来自: 140.112.196.111 (01/11 11:10) ※ 编辑: xavier13540 来自: 140.112.196.111 (01/11 19:33) ※ xavier13540:转录至看板 NTUmed02 04/20 02:17