Journal of Chemical and Engineering Data, Vol.41, No.4, 900-905, 1996
Isochoric (P,Rho,T)-Measurements for Liquid Toluene from 180-K to 400-K at Pressures to 35-MPa
The (p,rho,T) relationships were measured for a specially purified sample of toluene by applying an isochoric method with gravimetric determinations of the amount of substance. Temperatures ranged from 180 K to 400 K, while pressures were up to 35 MPa. Measurements were carried out on 20 compressed liquid isochores at a total of 311 state conditions. Saturated liquid densities were estimated by extrapolating each isochore to the vapor pressure, and determining the temperature and density at the intersection. Published (p,rho,T) data are in good agreement with this study. For the (p,rho,T) apparatus, the expanded uncertainty (at the 2 sigma level) of the temperature is +/-0.03 K, and for pressure it is +/-0.01% at p > 3 MPa and +/-0.05% at p < 3 MPa. The principal source of uncertainty is the cell volume (28.5193 cm(3) at 0 K and 0 MPa) which has an estimated statistical uncertainty (at the 1 sigma level) of +/-0.003 cm(3). When the sources of uncertainty are combined, the expanded uncertainty (at the 2 sigma level) of the density values is estimated to be +/-0.05%.