关于第54届国际化学奥林匹克试题4-9的表观解离常数计算的讨论

doi:10.3866/PKU.DXHX202210014

Abstract

Abstract:

Chemical equilibrium contains information on the extent of reaction, which is an important part of physical chemistry. In the context of the solvation of lithium polysulfide in lithium-sulfur batteries, Q4-9 of the 54th International Chemistry Olympiad (IChO) examined students' understanding and calculation of the apparent equilibrium constant of the reaction in the equilibrium system of multi conformational compounds. This article will discuss how to apply the weighted average of the free energy of the two conformations of lithium polysulfide to calculate the apparent equilibrium constant from the perspective of thermodynamics and statistical physics.

Key words: Chemical equilibrium, Thermochemistry, Equilibrium constant, Polysulfide

Sihan Zhang, Chiyu Liang, Xiaohang Qiu. Discussion on the Calculation of Apparent Dissociation Constant in Problem 4-9 of the 54th International Chemistry Olympiad[J].University Chemistry, 2022, 37(12): 2210014.

Figures/Tables 4

References 9

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数据来源	ΔG_app/(kJ?mol^?1)	K_app
方程(1) ^[5]	20.10	3.01 × 10^?4
方程(3)	21.68	1.59 × 10^?4
电导率法^[9]	–	1.69 × 10^?4

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Discussion on the Calculation of Apparent Dissociation Constant in Problem 4-9 of the 54th International Chemistry Olympiad

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