异丙醇-环己烷双液系相图实验中的几点探讨和误差分析  

Discussion and Error Analysis on Phase Diagram Experiment of Isopropanol-cyclohexane Two-liquid System

作　　者：姚英 丁莉峰 靳福泉 Yao Ying;Ding Lifeng;Jin Fuquan(Taiyuan Institute of Technology(Department of Chemistry and Chemical Engineering),Taiyuan Shanxi 030008,China)

机构地区：[1]太原工业学院(化学与化工系),山西太原030008

出　　处：《山西化工》2024年第3期85-87,共3页Shanxi Chemical Industry

基　　金：山西省研究生教育教学改革课题(2021YJJG321);山西省高等学校科技创新项目(2021);山西省教学厅高等学校教学改革创新项目(J2019199);山西省一流本科专业建设点建设——应用化学专业(2020)资助。

摘　　要：异丙醇-环己烷双液系相图是大学物理化学实验中关于相平衡知识运用的一个实验项目。本文对实验过程中几个值得推敲的问题从理论上进行深度分析。解析清楚后,更便于学生深刻理解实验原理,明白哪些具体操作会带来实验误差,哪些操作即便不准确也不会造成实验结果有偏差。结果表明:在具体形状的圆底烧瓶里加热异丙醇和环己烷两组分系统,能得到固定沸点;加工圆底烧瓶时应在保证能取液分析的前提下尽可能小,以免小槽内液体的组成与待测气相组成偏差过大;固定外压下,恒沸点及恒沸组成固定;每次为了改变系统组成加入一定量的异丙醇时,实际移取液体体积与设定体积若有偏差,对绘制相图并无影响。The phase diagram of the isopropanol-cyclohexane two-liquid system is an experimental project on the application of phase equilibrium knowledge in the physical chemistry experiment.In this paper,several problems in the course of the experiment are deeply analyzed theoretically.After the analysis clearly,it is more convenient for students to understand the experimental principle deeply,which concrete operation will bring the experimental error,which operation will not cause the experimental result to have the deviation even if it is not accurate.The results show that the constancy boiling point can be obtained by heating the two-component system of isopropanol and cyclohexane in a round bottomed flask.When processing round bottom flask,it should be as small as possible under the premise that liquid can be taken out for analysis,so as to avoid the large deviation between the liquid composition in the tank and the gas composition to be measured.Under the fixed external pressure,the constant boiling point and the constant boiling composition are constancy.Every time a certain amount of isopropanol is added in order to change the composition of the system,the deviation between the actual volume of the liquid removed and the set volume has no effect on the phase diagram.

关 键 词：物理化学 双液系相图 误差分析 

分 类 号：O6-33[理学—化学]