A new method to estimate equilibrium phase distribution ratios (K values) improves on the shortcomings of older methods. The method is based on the generalized fugacity charts of Lewis, Kay, and Newton, and uses reduced temperatures and pressures as parameters.A third-degree polynomial is prepared from Lu’s chart for calculating liquid molarity, which is used for calculating liquid phase fugacity from fugacity of saturated liquid. The proposed method, therefore, requires looking up only one chart-the generalized fugacity chart (which is a well-spaced-out chart and can be read accurately) and the rest of the calculations use equations, thus enabling rapid calculation.This article als...