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作者在7具不同温度(5°,10°,15°,20°,25°,30°,35°)下,研究了乙酸乙酯和氢氧化钠在二氧六圜和水的混合溶剂中的反应速度。每个温度有7个不同的二氧六圜和水的成分(0%,5%,10%,15%,20%,25%,30%的二氧六圜),因此得到49个速度常数。在每个温度里,反应速度常数随溶剂介电常数的减小而略为下降:温度愈高,下降趋势愈为显著。同溶剂成分的活化能随着溶剂里二氧六圜成分的增加而略为下降。同介电常数的活化能,在80至50的介电常数范围中,却和介电常数的变化无关。它的平均值是11300卡。我们用实验结果检验最近三个溶液里离子和分子反应速度理论:(1)Moelwyn-Hughes 的、(2)Laidler-Eyring 的和(3)Amis-Jaffe 的理论。就介电常数对反应速度的影响来说,理论(1)和(2)在质上就不和实验相符。理论(3)在质上似和实验相符,但在量上却相差太远。因此就乙酸乙酯对氢氧化钠的反应来说,三个理论都是不合的。
The authors studied the effect of ethyl acetate and sodium hydroxide in a mixture of dioxane and water at seven different temperatures (5 °, 10 °, 15 °, 20 °, 25 °, 30 °, 35 °) The reaction speed. There are seven different dioxane and water components (0%, 5%, 10%, 15%, 20%, 25%, 30% dioxane) at each temperature, resulting in 49 velocity constants . At each temperature, the reaction rate constant decreases slightly with the decrease of the dielectric constant of the solvent: the higher the temperature, the more the downward trend becomes. The activation energy of the solvent composition decreases slightly with the increase of the dioxane fraction in the solvent. The activation energy of the same dielectric constant, in the dielectric constant range of 80 to 50, has nothing to do with the change of the dielectric constant. Its average is 11300 cards. We use the experimental results to examine the theory of ionic and molecular reaction velocities in the last three solutions: (1) Moelwyn-Hughes, (2) Laidler-Eyring, and (3) Amis-Jaffe’s theory. Theoretically (1) and (2) are qualitatively not experimental in terms of the effect of dielectric constant on the reaction rate. Theorem (3) is qualitatively consistent with the experiment, but far outweighed by the amount. Therefore, the reaction of ethyl acetate on sodium hydroxide, the three theories are not compatible.