Solidifying point determining device

Abstract

The invention relates to a solidifying point determining device which comprises an ice bath device, a refrigeration device and a cold trap where an ice bath tank is arranged. The ice bath device comprises the ice bath tank, a determining pipe, a determining pipe stirring rod which is inserted into the determining pipe and an ice bath tank stirring rod which is inserted into the ice bath tank, wherein the determining pipe is outwards communicated with a feeding branch pipe which inclines upwards, the feeding branch pipe is arranged between an air sleeve plug and a determining pipe upper cover, and a branch pipe plug for sealing the feeding branch pipe is arranged at the top end of the feeding branch pipe. The refrigerating device comprises a compressor, a condenser, a capillary tube and a coiled tube type evaporator, wherein the compressor, the condenser, the capillary tube and the coiled tube type evaporator are sequentially and circularly connected through a refrigerating fluid pipeline. A magnetic stirrer is arranged on the lower side of the bottom of the cold trap. The solidifying point determining device further comprises a digital backmann thermometer, an electric control device and an ice bath temperature sensor. The invention further discloses a method for determining a solidifying point through the solidifying point determining device. The solidifying point determining device has the advantages that an experiment temperature and the stirring speed can be conveniently controlled and a serious surfusion phenomenon can be avoided.

Description

Technical field [0001] The invention belongs to the technical field of thermal analysis and relates to a freezing point measuring device. Background technique [0002] The freezing point is an important physical and chemical parameter of a substance, and it is of great significance to determine the freezing point of a substance. The measured value of the freezing point of the solvent and the solution can also be used to calculate the molecular weight or molar mass of the solute. [0003] The freezing point depression method is one of the classic methods for determining the molecular weight of substances. The principle is based on the colligative nature of the dilute solution, that is, for the solution formed by the solute that does not volatilize, dissociate, polymerize, and does not form a solid liquid with the solvent, the freezing point depression method is used to determine the molar mass. The range of use is non-volatile and non-volatile. Dilute solution of electrolyte mater...

AI Technical Summary

Problems solved by technology

The key to the success or failure of the freezing point determination experiment is to control the degree of supercooling and the stirring rate. Therefore, the traditional experimental method has the following shortcomings: (1) The experimental temperature cannot be easily controlled, which may lead to serious supercooling of the measured solution or insufficient refrigeration. (2) Relying on manual stirring is not only inconvenient to control the stirring speed, but also may touch the inner wall of the measuring tube and the thermometer during the stirring process, and there is a risk of collision damage

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