课程名称︰普通化学丙 课程性质︰系定必修 课程教师︰周必泰 开课学院：医学院 开课系所︰医学系 考试日期（年月日）︰971121 考试时限（分钟）：120 是否需发放奖励金：是 （如未明确表示，则不予发放） 试题 : General Chemistry Midterm Examination 2008/11/21 (Total Score 200) 1. Definition and Explanation (80%) 1-1 Please write the formula and full name of atom: 砷，磷，氪，钾，氙 Example: 氧 O oxygen (10) 1-2 Explain ultraviolet catastrophe.(5) Explain Pauli exclusion priciple.(5) 1-3 Light has duality, namely particle like and wave like. Provide one experi- mental result for each case.(5) 1-4 Give three experimental results that cannot be explained by the classical mechanics.(5) 1-5 Explain why the molar heat capacity (Cv) of most mono atomic metal is ~3R at room temperature (Pierre-Louis Dulong and Alexis-Therese Petit rule), while Cv is ~0 when temperature is close to 0 K.(5) 1-6 Based on standing wave and de Broglie relation briefly explain energy le- vels have to be quantized when treating the particle motion in a circle as a wave in a fixed radius r where potential energy = 0.(10) 1-7 In one dimensional vibrational motion for a diatomic molecule AB (with mass Ma for A atom and Mb for B atom) along the x axis where the potential ener- gy is assumed to be (1/2)kx^2 (k = force constant), write down the Hamilto- nian for the Schrodinger equation.(10) 1-8 At 0 K, should the molecule be frozen? If not, explain your answer.(5) Can you link this question with Heisenberg's uncertainty principle?(5) 1-9 Define hydrogen-like atom(3) and isoelectronic ion(2). 1-10For the A4 family, CO2 gas is a prevailing species on the earth, however, SiO2 gas is rarely observed. Explain.(5) 1-11Define the electrophilic and nucleophilic reagent.(5) Is BF3 an electrophi- lic or neucleophilic reagent? Explain.(5) 2.Question(120%) 2-1. For 1s orbital, Ψ1s = [(1/√π)(Z/a0)^(3/2)] [e^(-Zr/a0)], where a0 = 0.529埃, find out the radius for maximum probability for He^+ .(10) 2-2. Draw Lewis structure of XeF2.(5) What type of hybridization orbital for Xe in XeF2?(5) How many translation, rotation, and vibration motions for XeF2?(5) 2-3. Calculate the energy per photon (in terms of joule(3) and wave number(5)) and energy per mole of photons (in terms of kcal/mol(5)) for radiation of wavelength at 400 nm. (h=6.62 x 10^(-34) Js, c=3x10^8 m/s) 2-4. For A1 family (Li, Na, K, Rb and Cs), please predict the trend in reducing ability in the gas (or in the solid state).(3) However, in aqueous soluti- on, the order of reducing ability is Li > K > Na. Explain.(2) However, so- dium and potassium react much more vigourously with water. Explain.(5) 2-5. Assume that the MOs of the OH radicle result from the overlap of 2pz (for oxygen) and 1s orbital of the hydrogen (the O-H bond lies along the z ax- is). (15) a. Draw the MO energy diagram for OH. Place the correct number of elect- rons in the energy levels. b. Estimate the bond order for OH. c. Predict whether the bond order of OH+ is greater than, less than. or the same as that of OH. Explain. 2-6. OCN- and CNO- are isomers. Write down the most stable Lewis structure for OCN- and CNO-.(5) Determine and explain which one (OCN- or CNO-) is a mo- re stable form.(5) 2-7. Order the following species with respect to the carcon-oxygen bond length (longest to shortest). Explain.(10) 2-8. Based on the MO theory, arrange the following from lowest to highest ion- ization energy: O, O2, O2-, O2+. Explain your answer.(10) 2-9. According to the NMR spectrum shown below, answer the following questions. (给了一张NMR的图)The intensity ratio of a:b:c is calculated to be 3:2:3. 1. Draw the structure of TMS, and uses TMS as a reference?(5) 2. Which of the following compounds is suitable for the above NMR spectr- um? And assign a, b, and c peaks in the spectrum to the respective hy- drogen.(10) 1. H H H │ │ │ H─C─C─C─C─H │ ∣ ∥ ∣ H H O H 2. H H H ∣ ∣ ∣ H—C—C—C—C—Br ∣ ∣ ∥ ∣ H H O H 3. H H H H ∣ ∣ ∣ ∣ H—C─C─C─C＝O ∣ ∣ ∣ H H H 4. H Br H │ │ │ H─C─C─C─C─H │ │ ∥ ∣ H H O H 5. H CH3 │ │ H─C─C─C─H │ │ ∥ H H O 2-10.For linear molecule, the rotational energy is given by h^2 E = ───── J(J+1) J (8π^2)I I= μR ^2 e μ:reduced mass Re:average (equilibrium) bond length 1 35 The bond length of H Cl is 126 pm. Calculate the required electromagne- tic radiation for the rotational transition from J=2 to J=3. (10) 2-11.The vibrational potential energy surface is shown as below. Explain why the potential is anharmonic rather than harmonic?(5) Why the energy spac- ing decreases and becomes continuous after dissociation?(5) --

※ 发信站: 批踢踢实业坊(ptt.cc) ◆ From: 140.112.241.54