大学化学 >> 2017, Vol. 32 >> Issue (4): 61-67.doi: 10.3866/PKU.DXHX201609019

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关于球形小液滴热力学公式及其气液平衡条件的讨论

李爱昌*(),赵娣   

  • 发布日期:2017-04-20
  • 通讯作者: 李爱昌 E-mail:aichangli@hotmail.com

Discussion on Thermodynamic Formula and the Gas-Liquid Equilibrium Condition for Spherical Droplet

Ai-Chang LI*(),Di ZHAO   

  • Published:2017-04-20
  • Contact: Ai-Chang LI E-mail:aichangli@hotmail.com

摘要:

依据热力学第一和第二定律,从不同角度导出了球形小液滴的热力学基本公式。明确指出公式中的压力为液体相的压力,不是气相压力。分别用熵判据和Gibbs自由能判据证明了小液滴的气液相平衡条件为物质在两体相的化学势相等。强调指出:相平衡条件具有普适性,与是否为孤立体系或封闭体系及其类型无关,不仅适于球形液滴,对其他形状的液体也适用。对文献中存在的相关问题进行了较详细的讨论,澄清了一些容易模糊的认识。

关键词: 球形液滴, 热力学基本公式, 相平衡条件

Abstract:

Thermodynamic formula for the spherical droplet was obtained from the different analysis aspect based on the first/second law of thermodynamic. It should be pointed out that the pressure in formula is liquid pressure, but not gas pressure. According to the entropy and Gibbs free energy criteria, it was proved that the vapor-liquid equilibriumcondition is that the chemical potentials of two bulk phase are equal. It is noted that the phase equilibrium condition can not only be applied for the spherical droplet, but also for others shape droplets, and whether it is isolated system or a closed system and the type. In addition, the relevant problems in the literatures were discussed in detail and some obscure opinions were clarified.

Key words: Spherical droplet, Thermodynamic formula, Phase equilibrium condition

MSC2000: 

  • G64