共查询到19条相似文献,搜索用时 156 毫秒
1.
2.
密度法测定了298.15 K下乙醇、环己烷、三氯甲烷、甲苯、丙酮、四氯化碳、乙腈、二甲基甲酰胺、二甲基亚砜在甲醇或苯及两者混合物中的无限稀释偏摩尔体积. 密度测定所用溶液中溶质的浓度范围是0.2一1.5 m; 甲醇和苯混合物是全组成比范围. 溶质偏摩尔体积随甲醇-苯组成比的变化趋势反映了几种分子间相互作用结果即三种分子间物理型分子间相互作用; 溶质与甲醇分子氢键缔合相互作用; 溶质同甲醇或苯的弱络合作用。 相似文献
3.
4.
甲酰胺、乙酰胺、尿素在两种极性非水溶剂中的体积性质 总被引:1,自引:0,他引:1
以尿素、甲酰胺和乙酰胺为溶质,二甲基甲酰胺和二甲基亚砜为溶剂;或以二甲基甲酰胺、二甲基亚砜为溶质,以甲酰胺为溶剂,通过测定溶液在298.15K下的密度数据,求得了溶质的表观摩尔体积以及与溶质-溶质相互作用相关的体积第二维里系数.利用定标粒子理论讨论了溶质分子的几何体积、溶质-溶剂相互作用对溶质偏摩尔体积的影响,结果表明,溶质的溶剂化与溶质-溶质相互作用的体积效应呈相反的变化趋势 相似文献
5.
NaCl、KCl在蔗糖水溶液中的粘度 总被引:2,自引:0,他引:2
报导了在298.15及308.15K下,NaCl、KCl在含有蔗糖5,10,15,20,25%(质量分数w)的水溶液中的密度及粘度数据.计算了在无限稀释条件下,NaCl和KCl在该体系中的粘度B系数及偏摩尔体积.结果发现:两种电解质的B系数随蔗糖含量的增加及温度的升高而增大且对蔗糖水溶液的结构起破坏作用.讨论了该三元体系内部溶质-溶质、溶质-溶剂间的相互作用,同时应用流动过渡状态理论计算了两种电解质在各组成下蔗糖水溶液中的流动活化参数 相似文献
6.
7.
甲酰胺,乙酰胺,尿素在两种极性非水溶液中的体积性质 总被引:2,自引:2,他引:0
以尿素、甲酰胺和乙酰胺为溶质,二甲基甲酰胺和二甲基亚砜为溶剂;或以二甲基甲酰胺、二甲基亚砜为溶质,以甲酰胺为溶剂,通过测定溶液在298.15K下的密度数据,求得了溶质的表观磨尔体积以及与溶质-溶质相互作用相关的体积第二维里系数。利用定标粒子理论讨论了溶质分子的几何体积、溶质-溶剂相互作用对溶质偏摩尔体积的影响,结果表明,熔质的溶剂化与溶质-溶质相互作用的体积效应呈相反的变化趋势。 相似文献
8.
9.
10.
11.
《Fluid Phase Equilibria》2002,198(1):131-145
Densities of 1-propanol+water+lithium nitrate mixtures have been measured with an oscillating-tube densimeter over a large range of concentrations of the salt and 1-propanol, at 288.15, 298.15, 308.15, and 318.15 K. From these densities, apparent molar volumes of lithium nitrate in 1-propanol+water mixtures have been calculated for each temperature, and apparent molar volumes at infinite dilution have been evaluated. An empirical correlation for partial molar volumes of lithium nitrate in 1-propanol+water mixtures with solvent composition and temperature has been derived. 相似文献
12.
Xiao Gang ZHANG Hai Fei ZHANG Bu Xing HAN* Bao Ke ZHANG Qing HUO Center for Molecular Sciences Institute of Chemistry Chinese Academy of Sciences Beijing Institute of Chemistry Engineering Beijing United University Beijing 《中国化学快报》2001,(1)
Supercritical fluids (SCFs) have many unique properties1. However, nearly all of the features are related with the aggregation or clustering of the molecules in the fluids. Some researchers have reported that the partial molar volumes (PMVs) of the solutes in dilute supercritical (SC) solutions are large negative values1-4, which is different from common liquid solutions. Negative PMV of a solute in SC solution results from the fact that the local density of the solvent surrounding the so… 相似文献
13.
Henryk Piekarski Alina Piekarska Kinga Kubalczyk 《The Journal of chemical thermodynamics》2011,43(9):1375-1380
Heat capacities and speed of sound of (acetonitrile + 2-methoxyethanol) mixtures at 298.15 K and the densities of the same mixtures at T = (308.15 and 318.15) K were determined over the whole composition range. The excess of molar volume and isobaric heat capacity of the mixture, the partial molar volumes and heat capacities of both components of the mixture as well as the adiabatic and isothermal coefficients of compressibility and their excess were calculated from the obtained experimental data. The internal pressure of the examined system was also calculated. The results of investigations were analyzed and discussed. The behavior of the analyzed functions is similar to that observed in the case of the mixtures of acetonitrile with some aprotic solvents examined earlier. 相似文献
14.
Density of supercritical CO_2-tetrahydrofuran binary mixture and the partial molar volume of the cosolvent 总被引:1,自引:0,他引:1
The densities of supercritical CO2-tetrahydrofuran (cosolvent) binary mixture weremeasured at temperatures in range of 308.15 to 323.15 K and at pressure up to 16.5 MPa.The concentrations of tetrahydrofuran were from 0 to 0.57 mol/L.The partial molar volume of tetrahydrofuran was calculated based on the relationship between the density of the mixture and the concentration of the cosolvent.It is observed that the partial molar volume of the cosolvent is negative and the absolute value decreases with increasing pressure and the concentration of the cosolvent. 相似文献
15.
Muvva Raghavendra M. Gowrisankar T. S. Krishna A. Venkatesulu 《Journal of solution chemistry》2018,47(4):684-704
Densities (ρ), speeds of sound (u), and viscosities (η) are reported for binary mixtures of 2-methylaniline with substituted ethanols (2-phenylethanol, 2-chloroethanol and 2-aminoethanol) over the entire composition range of mole fraction at T?=?(303.15–318.15) K and at atmospheric pressure, 0.1 MPa. The excess molar volume, excess isentropic compressibility and deviation in viscosity are calculated from the corresponding experimental densities, speeds of sound and viscosities. The excess properties are correlated using the Redlich–Kister polynomial smoothing equation. Excess partial molar volumes and excess partial molar isentropic compressibilities were calculated for all the binary systems throughout the composition range and also at infinite dilution. The variations in these properties with composition, for all the binary mixtures, suggest that loss of dipolar association, difference in size and shape of the component molecules, dipole–dipole interaction and hydrogen bonding between molecules of 2-methylaniline with 2-phenylethanol, 2-chloroethanol and 2-aminoethanol are involved. 相似文献
16.
M. A. Iglesias-Otero J. Troncoso E. Carballo L. Romaní 《Journal of solution chemistry》2007,36(10):1219-1230
Refractive indices at 298.15 K and densities in the temperature interval 293.15 to 318.15 K were determined at atmospheric
pressure over the whole composition range for the binary systems [Bmim][BF4]+(methanol, or 1,3-dichloropropane, or dimethyl carbonate). Due to the high viscosity of the samples, which would produce
a wrong density if a classical vibrating-tube densimeter were used, a densimeter was employed that automatically corrects
the data for the viscosity effect. Because at room temperature some [Bmim][BF4]+dimethyl carbonate mixtures showed partial immiscibility, liquid-liquid equilibrium was determined for this system. Excess
molar volumes and deviations of refractive index from linear mixing behavior were calculated from the experimental data.
An erratum to this article can be found at 相似文献
17.
Jorge G. Ganopolsky Hugo L. Bianchi Horacio R. Corti 《Journal of solution chemistry》1996,25(4):377-389
The densities of boric acid aqueous solutions and sodium hydroxide-sodium borate mixtures were measured as a function of concentration, between 375 and 523 K at pressures close to saturation. The partial molar volumes of boric acid were obtained and it was found that they are almost independent of the concentration. The partial molar volumes of the sodium hydroxide-sodium borate mixtures were fitted to the Pitzer equation for mixtures using the known parameters for NaOH. Thus, the partial molar volume at infinite dilution and the Pitzer parameters of sodium borate could be obtained by assuming ideal mixing. 相似文献
18.
IntroductionTherehasbeenanincreasedinterestinthethermodynamicbehaviorofternarymixtures(water+nonaqueoussolvent+electrolyte)[1].However,therehasbeenashortageofinvestigationsonsuchmixtures,especiallyonaromaticsolutesthatcontainthesubstituent.Littleiskn… 相似文献
19.
G. I. Egorov D. M. Makarov 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2008,82(10):1778-1784
The densities of ethylene glycol-dimethylsulfoxide binary mixtures were measured over the temperature range 278–323.15 K at atmospheric pressure using a vibrational densimeter. The excess molar volumes, apparent molar volumes, partial molar volumes of mixture components, volumetric thermal expansion coefficients, and partial molar volumetric thermal expansion coefficients were calculated. The excess molar volumes were described by the Redlich-Kister equation, and the partial molar volumes were calculated by two methods. The density-composition dependence contained a weak maximum, which disappeared as the temperature increased. The excess molar volumes were negative, and deviations from ideality increased as the temperature grew. 相似文献