Isochoric Heat Capacities of Ethanol-Water Mixtures at Temperatures from 280 K to 420 K and Pressures to 30 Mpa

Published

October 12, 2021

Author(s)

Hiroshi Kitajima, N Kagawa, S Tsuruno, Joe W. Magee

Abstract

Specific heat capacity at constant volume is one of the most important thermodynamic properties to develop and evaluate thermodynamic equations of state. With this viewpoint, isochoric heat capacities of ethanol-water mixtures have been measured with a twin cell type adiabatic calorimeter developed at the National Defense Academy. Temperatures were measured with a platinum resistance thermometer on the bottom of each cell and were reported on the ITS-90. Sample pressure measurements were made with a quartz crystal transducer. Densities were calculated from the volume of the calorimeter cell and sample mass. The experimental expanded uncertainty (with a coverage factir k=2) of temperature measurements is ± 13 mK, and that of pressure measurement is +or-} 8k Pa. The expanded relative uncertainty for isochoric heat capacity is estimated to be ± 2% for liquid phase measurements, and for density it is + or-} 0.16%. The present measurements for xC₂H₅OH + (1-x) H₂O} with x = (0.104, 0.253, 0.498 and 0.755), were obtained at temperatures ranging from 280 to 420 K and at pressures up to 30 Mpa.

Conference Dates

December 4-5, 2005

Conference Location

Kobe, 1, JA

Conference Title

Proc. Asian Conference on Refrigeration and Air Conditioning

Pub Type

Conferences

Keywords

density, ethanol, isochoric heat capacity, mixtures, thermodynamic property, water

Citation

Kitajima, H. , Kagawa, N. , Tsuruno, S. and Magee, J. (2021), Isochoric Heat Capacities of Ethanol-Water Mixtures at Temperatures from 280 K to 420 K and Pressures to 30 Mpa, Proc. Asian Conference on Refrigeration and Air Conditioning, Kobe, 1, JA (Accessed October 14, 2025)