This document presents equations for calculating various thermodynamic properties of binary mixtures including: 1) The binary interaction parameter Bij used in calculating excess Gibbs energy from a combination of an ideal term and a non-ideal term weighted by wij. 2) The thermal conductivity Tcij of a binary mixture as the geometric mean of the components' thermal conductivities weighted by their mole fractions. 3) The pressure Pcij as a function of the mixture's compressibility factor Zcij, thermal conductivity, and molar volume which is the geometric mean of the components' molar volumes. 4) Equations for calculating the natural logarithm of fugacity coefficients for the two components as functions of

1. 𝐵𝑖𝑗 =
𝑅𝑇𝑐 𝑖𝑗
𝑃𝑐 𝑖𝑗
(𝐵0
+ 𝑤𝑖𝑗 𝐵1
) ; 𝑇𝑟𝑖𝑗 =
𝑇
𝑇𝑐 𝑖𝑗
𝑤𝑖𝑗 =
𝑤𝑖 + 𝑤𝑗
2
𝑇𝑐𝑖𝑗 = (𝑇𝑐𝑖 𝑇𝑐𝑗)
1
2(1 − 𝑘𝑖𝑗)
𝑃𝑐𝑖𝑗 =
𝑍𝑐𝑖𝑗 𝑅𝑇𝑐𝑖𝑗
𝑉𝑐𝑖𝑗
𝑍𝑐𝑖𝑗 =
𝑍𝑐𝑖 + 𝑍𝑐𝑗
2
𝑉𝑐𝑖𝑗 = [
𝑉𝑐𝑖
1
3⁄
+ 𝑉𝑐𝑗
1
3⁄
2
]
3
𝑙𝑛𝜑̂1 =
𝑃
𝑅𝑇
( 𝐵11 + 𝑦2
2
𝛿12)
𝑙𝑛𝜑̂2 =
𝑃
𝑅𝑇
(𝐵22 + 𝑦1
2
𝛿12)