外推法测定甘油和硼酸反应平衡常数

Using Extrapolation to Determine the Equilibrium Constant of the Reaction of Glycerol and Boric Acid

探索了利用电位法[1]测定甘油和硼酸反应的平衡常数。在不同浓度下,甘油与硼酸反应生成硼酸甘油酯,通过电位法测定溶液的pH值,间接测定硼酸甘油酯的含量,通过逐步逼近法,外推到浓度接近零时的平衡常数,得到甘油与硼酸反应的平衡常数为K=3.0×1-0 9。

This article explores the way of using electropotential method to determine the equilibrium constant of the reaction of glycerol and boric acid. Of different concentration ,glycerol can react with boric acid to form glyceroborate. By means of electropotential method,the PH of the solution is determined. Then the content of glyceroborate can be determined indirectly. Through the way of gradual approaching,when the concentration approaches to zero, the equilibrium constant can be got by extrapolation ,that is k= 3.0× 10^-9.