Abstract
Five non-linear and three polynomial isothermal equations of state for liquids have been tested for their performance in describing the data of the density and the isothermal compressibility of benzene and cyclohexane from 288 to 323 K up to the melting pressures, and of methanol and ethanol between 273 and 333 K up to 280 MPa. It is found that the best representation is given by an expansion in temperature and density and the second best by the Usual Tait equation. The coefficients of these two equations for the four organic liquids are obtained by fitting the experimental data by a least squares analysis.