ABSTRACT Physicochemical properties comprising densities (ρ), speed of sound (u) and refractive indices ( for [EMIM]⁺[EtSO4]⁻, pentanoic acid, 2-methylpropanoic acid and binary mixtures containing {[EMIM]⁺[EtSO4]⁻ + pentanoic or 2-methylpropanoic acid} were determined across the entire mole fraction range of concentrations from 0.1 to 1.0 at T = 288.15 K to 313.15 K, under atmospheric pressure. The following thermodynamic properties: excess molar volumes (), isentropic compressibility and deviation in isentropic compressibility were computed from the measured and values. Furthermore, together with for the binary systems were negative over the entire mole fraction range at fixed temperature but increases with increasing temperature. The Redlich-Kister polynomial equation was used to correlate the derived properties with resulting values. The results obtained from this study have been discussed in terms of intermolecular interactions, H-bonding, ionic interactions and dipole moments in the binary mixtures of the ionic liquid and carboxylic acids.

中文翻译：

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1-乙基-3-甲基咪唑乙基硫酸盐离子液体及其与戊酸或2-甲基丙酸的二元混合物在不同温度下的热物理和热力学性质

摘要 物理化学性质包括密度 (ρ)、声速 (u) 和折射率（对于 [EMIM]⁺[EtSO4]⁻、戊酸、2-甲基丙酸和含有 {[EMIM]⁺[EtSO4]⁻ +戊酸或 2-甲基丙酸}在大气压下 T = 288.15 K 至 313.15 K 的整个摩尔分数范围内从 0.1 到 1.0 的浓度范围内测定。以下热力学性质：过量摩尔体积 ()、等熵压缩性和偏差等熵压缩率是从测量值和值计算出来的。此外，在固定温度下，二元系统在整个摩尔分数范围内都是负的，但随着温度的升高而增加。Redlich-Kister 多项式方程用于将导出的性质与结果相关联值。从这项研究中获得的结果已经在离子液体和羧酸的二元混合物中的分子间相互作用、氢键、离子相互作用和偶极矩方面进行了讨论。