山东大学 Physica| Chemistry(2)课程试卷 2018-2019学年Fa|学期 舞分[舞 分L Ill Give brief answer to the following questions:Totally 20 points) IV Calculation(totally 20 points): 13-1)(12 points)NHs can decompose on metal catalyst for preparation of hydrogen for +-1[12 points)At 298 K, the dependence of surface tension of alcohol solution on molarity industry use. The decomposition rate law is found to be r=k PNh concentration(mol dm")isa(mN m")=728-0.5c (I) Calculate the surface cohol on the solution surface when cao.6 mol dm (1)14 points] Please give explanation to this fact based the competing adsorption of NHs and Ta-c(da)=1.46x10-5mol m2 Ha on the catalyst. (2)[4 points] Compare the adsorption coefficient of NHs and H2 on the catalyst surface (2)Calculate the capillary rise of this solution in a glass capillary of 10-m in (3)(4 points] explain the changing tendency of the order of the reaction. Assuming complete wettable and the density of solution of 0.986x10 kg m3, (1) 2)The adsorption coefficient of Hz is much stronger than that of NH3. (3)Change from l-order to no definite order to o-order (3)At what concentration will the surface excess of alcohol attain the maximum. 13-21(8 pints) It was found that the diffusion coeficient(D)of Fe(OH) colloidal particle is The maximum cannot be reached. about 1000 times less than Fel cation, but their mobilities (U) are close. Please give[1-2)(8 poins] For a colloidal particle of 4.2 nm in diameter, at 2981I K, the viscosity of 封 quantitative or semiquantitative explanation to these facts. the dispersion medium is r-0 00I Pa s. (1)The diffusion of Fe(OH)s colloidal particle is due to Brownian motion(the random (1)Calculate the diffusion coefficient of the colloidal particle, collision of water molecules), according to Einstein-Brownian diffusion law D=RT_,its RT= radius is about 1000 times larger than that of Fe". (2) Due to Brownian motion, what distance does this particle diffuse in one second? (2)For electric transfer, U-25,E2 tatic force exerted on tI x=√2D=1.02×105m colloidal particle is ca. 1000 times larger than Fe. 第2页共2页得分 阅卷人 III. Give brief answer to the following questions: (Totally 20 points) [3-1] [12 points] NH3 can decompose on metal catalyst for preparation of hydrogen for industry use. The decomposition rate law is found to be 3 2 NH H p r k p = . (1) [4 points] Please give explanation to this fact based the competing adsorption of NH3 and H2 on the catalyst. (2) [4 points] Compare the adsorption coefficient of NH3 and H2 on the catalyst surface. (3) [4 points] explain the changing tendency of the order of the reaction. (1) 3 3 3 3 2 2 NH NH NH NH H H 1 b p r k b p b p = + + means H H NH NH 2 2 3 3 b p b p  +1 , (2) The adsorption coefficient of H2 is much stronger than that of NH3. (3) Change from 1-order to no definite order to 0-order. [3-2] [8 pints] It was found that the diffusion coefficient (D) of Fe(OH)3 colloidal particle is about 1000 times less than Fe3+ cation, but their mobilities (U) are close. Please give quantitative or semiquantitative explanation to these facts. (1) The diffusion of Fe(OH)3 colloidal particle is due to Brownian motion (the random collision of water molecules), according to Einstein-Brownian diffusion law 6 RT D r = , its radius is about 1000 times larger than that of Fe3+ . (2) For electric transfer, r 0 2 3 U     = , the electrostatic force exerted on the colloidal particle is ca. 1000 times larger than Fe3+ . , 得分 阅卷人 IV. Calculation (totally 20 points): 4-1 [12 points] At 298 K, the dependence of surface tension of alcohol solution on molarity concentration c (mol dm-3 ) is 1 (mN m ) 72.8 0.5c − = − . (1) Calculate the surface excess of alcohol on the solution surface when c = 0.6 mol dm-3 . p c d RT dc     = −     =1.4610-5 mol m-2 (2) Calculate the capillary rise of this solution in a glass capillary of 10-3 m in radius. Assuming complete wettable and the density of solution of 0.986103 kg m-3 , gravity acceleration g = 9.80 N kg-1 . 2 cos h gR    = =1.50 cm (3) At what concentration will the surface excess of alcohol attain the maximum. The maximum cannot be reached. [4-2] [8 poins] For a colloidal particle of 4.2 nm in diameter, at 298.1 K, the viscosity of the dispersion medium is =0.001 Pa s. (1)Calculate the diffusion coefficient of the colloidal particle; 6 RT D r = =5.210-11 m2 s -1 (2) Due to Brownian motion, what distance does this particle diffuse in one second? x Dt = 2 =1.0210-5 m 山东大学 Physical Chemistry (2) 课程试卷 学院 专业 级 学号 姓名 … … … … … … … … … … … … … … 密 … … … … … … … … … … 封 … … … … … … … … … … 线 … … … … … … … … … … … … … 第 2 页 共 2 页 2018-2019 学年 Fall 学期