Density and speed of sound measurements of 1- and 2-butanol

The density and speed of sound of 1- and 2-butanol have been measured with two instruments; both instruments used vibrating-tube sensors for measuring density. At ambient pressure (83 kPa), density and speed of sound were measured from 278.15 K to 343.15 K. Adiabatic compressibilities were derived from these density and speed of sound data. Compressed liquid density measurements were carried out in a second instrument over a range from 270 K to 470 K with pressures from 0.5 MPa to 50 MPa. The measured density data were correlated with a modified Tait equation within their experimental uncertainty, and this correlation provides a baseline for extensive comparisons with literature data. Differences between the measured macroscopic properties of the two butanol isomers are related to differences on the molecular level. These were characterized by quantum mechanical calculations using the second-order Møller-Plesset model with the polarization basis set 6-311+G⁎⁎.