Heat Capacity Measurements of 13 Methyl Esters of n-Carboxylic Acids from Methyl Octanoate to Methyl Eicosanoate between 5 K and 350 K

Molar heat capacities of 13 methyl esters of the linear carboxylic acids from methyl octanoate to methyl eicosanoate were measured from 5 K to 350 K. The derived thermodynamic functions Sabs,m(T) and Hm(T) − H(0) were calculated. A correlation function for the absolute entropy at 298.15 K was found to be Sabs(n,298.15 K) = {215.94 + 31.517n} J·K-1·mol-1, with n being the number of carbon atoms in the parent carboxylic acid minus one. The heat capacity of the liquid phases in the temperature range of 250 K to 350 K can be described by Cp(n,T) = {103.16 + 16.273n + 0.04735n(T/K)} J·K-1·mol-1, with a mean absolute percentage deviation of 0.3%.

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