精華區beta NTU-Exam 關於我們 聯絡資訊
課程名稱︰普通化學甲下 課程性質︰ 課程教師︰彭旭明 開課學院:理學院 開課系所︰化學系 考試日期(年月日)︰2010/6/23 考試時限(分鐘):120min 是否需發放獎勵金:是 (如未明確表示,則不予發放) 試題 : Ι.Chemical Kinetics(36%) 1.For the reversible, one-step reaction 2A→B+C, the forward rate constant for the formation of B is 265 L‧mol^-1‧Min^-1 and the rate constant for reverse reaction is 392 L‧mol^-1‧Min^-1. The activation energy for the forward reaction is 39.7 kJ‧mol^-1 and that of the reverse reaction is 25.4 kJ‧ mol^-1.(8%) (a) What is the equilibrium constant for the reaction? (b) Is the reaction exothermic or endothermic? (c) What will be the effect of rasing the temperature on the rate constants and the equilibrium constant? 2.The following rate data were collected for the reaction 2A(g)+2B(g)+C(g)→ 3G(g)+4F(g):(8%) Initial concentration (mmol‧L^-1) ------------------------------------------------------------ Experiment [A]o [B]o [C]o Initial rate ((mmol G)‧L^-1‧S^-1) ------------------------------------------------------------ 1 10 100 700 2.0 2 20 100 300 4.0 3 20 200 200 16 4 10 100 400 2.0 5 4.62 0.177 12.4 ? ------------------------------------------------------------ (a) What is the order for each reactant and the overall order of the reaction? (b) Write the rate law of the reaction. (c) Determine the reaction rate constant. (d) Predict the initial rate for Experiment 5. 3.Which of the following plots will be linear?(5%) (a) [A] against time for a reaction first order in A. (b) [A] against time for a reaction zero order in A. (c) ln[A] against time for a reaction first order in A. (d) 1/[A] against time for a reaction second order in A. (e) k against temperature. (f) Initial rate against [A] for a reaction first order in A. (g) Half-life against [A] for a reaction zero order in A. (h) Half-life against [A] for a reaction second order in A. 4.The following schematic reaction profile is for the reaction A→D.(5%) | F | /\ G | E / \ /\ | /\ / \ / \ | / \-/ \ / \ Potential energy |A/ B \-- \ |- C \ | \ | \ D | \------- | |---------------------------------------- Reaction coordinate (a) Is the overall reaction exothermic or endothermic? Explain you answer. (b) How many intermediates are there? Identify them. (c) Identify each activated complex. (d) Which step is rate determining? Explain your answer. (e) Which step is the fastest? Explain your answer. 5.The rate law for the reaction between Ferrous and Thallic ions in acidic aqueous solution: 2Fe2+(aq)+Tl3+(aq)→Tl+(aq)+2Fe3+(aq) k[Fe2+]^2[Tl3+] is Rate (D,Fe2+)=------------------ [Fe2+]+k'[Fe3+] Propose a mechanism consistent with this rate law.(10%) Π.Coordination Chemistry (24%) 6.Which is the following complexes chiral?(4%) A A A A (a) | (b) | (c) | (d) | B------A C------D A------C C------B / | / / | / / | / / | / / / / / / / / / C------D B------A A------D B------A | | | | B C B C 7.Draw all the isomers of [Co(en)2(NO2)Cl]+ ion and specify which are linkage isomers, optical isomers and geometrical isomers, respectively.(8%) 8.Estimate the ligand field splitting for (a) [CrCl6]3- (λmax = 740nm), (b) [Cr(NH3)6]3+ (λmax = 460nm), and (c) [Cr(H20)6]3+ (λmax = 575nm), where λmax is the wavelength of the most intensely absorbed light. (d) Arrange the ligands in order of increasing ligand field strength.(6%) 9.(a)Sketch the d orbital energy-level diagrams for [MnCl6]4- and [Mn(CN)6]4-. (b)How many unpaired electrons are present in each complex? (c)Which complex absorbs the longer wavelongths of incident electromagnetic radiation? (6%) III.Main Groups Chemistry and Nuclear Chemistry(34%) 10.Draw the Lewis structure and give one reaction of elemental substances O, N, S, and P, respectively.(8%) 11.Describe the structure and bonding in B2H6.(6%) 12.The azide ion has an ionic radius of 148 pm and forms many ionic and covalent compounds that are similar to those of the halides. [The ionic radius: F-:133pm; Cl-:181pm; Br-:196pm; I-:220pm](8%) (a) Write the Lewis formula for the azide ion and predict the N-N-N bond angle. (b) On the basis of its ionic radius, where in Group 17/VII would you place the azide ion? (c) Compare the acidity of hydrazoic acid with those of the hydrohalic acids and explain any differences (for HN3:Ka=1.7*10^-5; HF:Ka= 3.5*10^-4). (d) Write the formulas of three ionic or covalent azides. 13.Sodium-24 (23.99096 Mu) decays to magnesium-24 (23.98504 Mu).(6%) (a) Write a nuclear equation for the decay. (b) Determine the change in energy that accompanies the decay. (c) Calculate the change in the binding energy per nucleon. 14.It is found that 2.0*10^-5 mol 222Rn (t1/2 = 3.82d) has seeped into a closed basement with a volume of 2.0*10^3 m^3. [Ci:3.7*10^10 disintegrations per second] (6%) (a) What is the initial activity of the randon in picocuries per liter (pCi‧Li^-1)? (b) How many atoms of 222 Rn will remain after 1 day (24h)? (c) How long will it take for the randon to decay to below the EPA recommended level of 4pCi‧L^Li? IV.Organic Chemistry (32%) 15. Draw all the isomers of C5H10 and name them. (10%) 16. Write the following structural formula: (6%) (a) Butanal (b) 3-hexanone (c) 2-heptanone (d) 2-ethyl-2-methylpentanal (e) 3,5-dihydroxy-4-octanone (f) 4,5-dimethyl-3-hexanone 17.The occurence of isotopes of some elements allows the presence of these elements to be readily identified in a mass spectrum of a compound. For example, Br has two naturally occurring isotopes with masses 79mu and 81mu, in the relative abundances 50% and 50%. In the bromination of methane, what are the mass spectra at parent peak for CH3Br, CH2Br, and CHBr3, respectively. (6%) 18.When propane is treated with chlorine gas, a mixture of compounds results. The mixture is separated and analysis of one of the components gives the 1H NMR spectrum shown here. Write the reaction and give the product. Interpret the NMR spectrum. (4%) (圖:習題19.91圖) 19.Draw the block diagrams of the following biopolymers:use monomers (e.g. ribose, amino acids, or glucose) as building blocks. (6%) (a) Protein (b) RNA (c) Starch -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 140.112.217.100