( p, ϱ, T) of {0.5C 8H 18+0.5(1-C 8H 16)}, {0.5(CH 3) 2CHCH 2C(CH 3) 3+0.5(1-C 8H 16) or 0.5C 8H 18}, and {0.333C 8H 18+0.333(1-C 8H 16)+ 0.333(CH 3) 2CHCH 2C(CH 3) 3}, in the range 298 to 373 K and 0.1 to 500 MPa

Abstract

The ( p, ϱ, T) behaviour has been determined at 298.15, 323.15, 348.15, and 373.15 K for {0.5C 8H 18 + 0.5(1-C 8H 16)} from 0.1 to 412 MPa, for {0.5(CH 3) 2CHCH 2C(CH 3) 3 + 0.5(1-C 8H 16)} from 0.1 to 291 MPa, and for {0.5(CH 3) 2CHCH 2C(CH 3) 3 + 0.5C 8H 18} from 0.1 to 500 MPa. Experimentally determined ( p, ϱ, T)s are also reported for {0.333C 8H 18+0.333(1-C 8H 16) + 0.333(CH 3) 2CHCH 2C(CH 3) 3} over the same temperature range up to 415 MPa. The experimental results are tabulated and the isothermal densities are represented by a quadratic equation for secant bulk modulus in terms of pressure and by the modified Tait equation. The temperature and pressure dependence of the excess molar volume is described.