※ [本文转录自 sleepychang 信箱] 作者: DahilSaIyo (爱乐人) 看板: NTU-Exam 标题: [试题] 97上 张焕宗 分析化学丁 期中考 时间: Tue Apr 7 22:07:18 2009 课程名称︰分析化学丁 课程性质︰系订必修 课程教师︰张焕宗 开课学院：医学院 开课系所︰医技系 药学系 海洋学程 考试日期（年月日）︰2009年4月6日 考试时限（分钟）：120分钟 (+30分钟) 是否需发放奖励金：是 （如未明确表示，则不予发放） 试题 : I Fill in the blanks (4 pt each, 64 pt total): 1. The ionic strhngth of 10ml of 1.0 M AgNO3 aqueous solution after adding 20ml pf 0.1M NaCl is __________ 2. Write down the mass-balance equation when dissolving CaC2O4 in 0.02M HCl. Solubility = [Ca(2+)] = C(H2C2O4) = ___________ 3. The solubility of Pb(IO3)2 in 0.02M Mg(NO3)2 (Ksp = 10^-13) is ______ if the effective diameters of Pb(2+) and IO3(-) are both 0.5 4. ________ is the main species of 10ml 0.1M phosphoric acid after adding 15ml 0.1M NaOH. 5. Glycine, without net migrating in electrophoresis, occurs at pH __________. (pKa and pKb of the glycine are 10.2 and 12.2) 6. Hydronium ion concentration in 1.0mM Na2HPO4 aqueous solution is __________ (Ka1=1.1 x 10^(-2);Ka2=7.5 x 10^(-8);Ka3=4.8 x 10^(-13) ) 7. If the pH is 7.5 after titrating 20ml of 0.1M H2A solution with 30ml of 0.1M NaOH, a possible pKa1 values of H2A is _________(+-)1. 8. A series of samples consisting of any possible combination of KCl, CaCl2 and NH4Cl is to be analyzed by adding AgNO3 to precipitate AgCl. What is the minimum volume of 10% w/v AgNO3 necessary to completely precipitate the chloride in any 1.0g sample? 9. Calculate the concentration of HPO4(2-) when dissolving 0.01 mole Na2HPO4 in aqueous solution (final pH = 7.0) 10. The pH of 0.2M Zn(NO3) is _________ when it dissolving to give 0.2M Zn(2+) (pKa = 9.0) and 0.40M NO3(-). 11. The pKa values for an acid H3A are 2.0, 5.0 and 9.0. The major species at pH = 3.0 is ___________ and at pH 7.0 is _______________. 12. A Base (B) has 2 pKb values of 4.0 and 9.0. The concentration of BH(+) at pH 8.0 is __________ and BH2(2+) at pH 3.0 is ____________ when saperately dissolving 0.01mole of the base in 1.0L of the buffers. 13. A 0.50ml aliquot of protein solution was digested, and the liberated NH3 was distilled into 10.0ml of 0.021M HCl. The unreacted HCl rerquires 3.20ml 0.02M NaOH for complete titration. If the protein contains 16.2%% nitrogen, the concentration of protein is ____________ mg/ml. 14. Suggest a method to determine Cl(-) in blood. ____________________________ II Differentiate the two terms in each pair (4 pt each, 40 pt total) 1. sampling and sample preparation 2. limit of detection and sensitivity 3. dynamic range and calibration curve 4. back titration and direct titration 5. standard solution and standardization 6. accuracy and precision 7. Fajan titration and Volhard titration 8. digestion and peptization 9. masking agents and reducing agents 10. equivalence point and end point III Nuetralization titration (4 pt each, 16 pt total) Titration of 20ml of 0.1M maleic acid (H2A, pKa1=2.2; pKa2=6.4) with 0.1M NaOH. What are the pH values of the solution after adding (A) 0; (B) 5; (C) 12; (D) 20ml NaOH? IV Precipitation (4 pt each, 20 pt total) 1. Define relative supersaturation of solutes. 2. How can you use it to control the particle size? 3. An approach to obtaining larger particles of Fe(OH)3. 4. (A) Is it possible to determine the concentration of I(-) and Br(-) in aq solution by tration with AgNO3? (B) Which one will be titrated first? V Buffer (4 pt each, 32 pt total) 1. Define the buffer capacity of a buffer solution. 2. How can you prepare a 0.1M buffer with pH 5.0? 3. Calculate (A) the concentration of H2PO4(-)[Ka1=1.1x10^(-2); Ka2=7.5x10^(-8) Ka3=4.8x10^(-13)] when dissolving Ag3PO4 [Ksp=3x10^(-18)] (B) Calculate the solubility of AgPO4 in the buffer. 4. (A) Write down the mass balance and (B) Charge balance; and calculate the concentration of (C) H2PO4- and (D) the solubility of Ag3NO4 in pure water. VI Internal standard vs. standard addition (4 pt each, 16 pt total) To determine Pb(2+) ions in blood using a spectrophotometer method, Cu(2+) ions was added as an internal standard. 1. Defferentiate internal standard and standard addition methods. 2. Is any reason for choosing Copper ions instead of lead ions? 3. How can you determine the concentration of lead ions in blood? 4. If a standard addition method is applied to determine Copper ions, how can it be used? VII Spiked recovery and detection limit (4 pt each, 12 pt total) Pure water containing no arsenic was spiked with 0.30μg arsenate/L. Eight replicate seterminations gave 0.28, 0.31, 0.29, 0.29, 0.32, 0.30, 0.29 and 0.32μg/L. Find 1. mean percent recovery of the spike 2. the concentration detection limit 3. the lower limit of quantitaion VIII Use a graph to answer each of the queation (4 pt each, 12 pt total) 1. Buffer capacity vs pH value. The HA has pKa 5.0 2. Titration curves of acids A and B (10.0ml;0.1M) with 0.1M NaOH. The pKa1 values of the two acids are both 3.0. The pka2 for the acid A and B values are 6.0 and 8.0 respectively. 3. The fraction off H2A and A(2-) oresent for acid A in question 2 against pH values. (结论是就算加了半小时总共考了两小时半还是没办法写完...) -- Work, as if you don't need money, Love, as if you've never been hurt, Dance, as if no one can see you, Sing, as if no one can hear. Live, as if the Earth was the Heaven...... --

※ 发信站: 批踢踢实业坊(ptt.cc) ◆ From: 140.112.222.213 ※ 编辑: DahilSaIyo 来自: 140.112.222.213 (04/10 21:20) ※ 编辑: DahilSaIyo 来自: 140.112.222.213 (04/10 21:20) -- 期末十大强片： 1.惊奇四修人 2.死当笔记本 3.不能过的秘密4.重修状 5.当二一来敲门 6.惊天动地59分 7.把学分找回来 8.十修微积 9.有学分真好 10.现在，很想当你 --

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