凝固点降低法测定摩尔质量实验装置的改进和应用

Improvement and Application of the Device for Determination of Molar Mass by Freezing Point Depression

针对现有物理化学实验“凝固点降低法测定物质的摩尔质量”的装置所存在的问题,本文对其进行了创新性的改进。我们设计了半导体制冷的金属冷阱和集成涡轮搅拌器与加热器的凝固点管,搭建了精密温度测量电路,并将各部分集成为成套设备。将改进的仪器应用于尿素-水、蔗糖-水、萘-环己烷等体系的测量。实验结果表明,相对现有的实验装置,改进仪器的测量结果重复性更好、准确性更高、实验效率更高,更加符合实验教学需求,有利于培养学生的创新思维和科研能力。

The experimental device of the physical chemistry experiment“Determination of the molar mass by freezing point depression”was innovatively improved to overcome the problems of the existing devices.A metal cold trap cooled by semiconductor chilling plates and a freezing point test tube integrated turbine agitator and heater were designed;a precise temperature measurement circuit was built.And each part was integrated into a complete set of equipment.The improved device was applied to the measurement of the urea-water,sucrose-water and naphthalenecyclohexane systems.The results show that compared with the existing experimental device,the improved device has better repeatability,higher accuracy,higher experimental efficiency,and is more in accord with the needs of laboratory teaching.And it is more beneficial to cultivating the innovative thinking and scientific research ability of students.