The relation of the parameters of the critical point of liquid-gas transition with the Boyle temperature

TL;DR

This paper reveals a precise relation between Boyle temperature, critical temperature, and compressibility factor for real substances, proposing a new way to determine critical volume using these parameters.

Contribution

It introduces a novel formula linking Boyle temperature and critical parameters to estimate the critical volume of liquids.

Findings

The ratio of Boyle temperature to critical temperature times critical compressibility factor is approximately 9.

The relation accurately predicts critical volume from Boyle temperature and critical pressure.

The proposed formula offers a new method to determine critical volume from measurable parameters.

Abstract

It is shown that the ratio of the Boyle temperature to the product of critical temperature and critical compressibility factor is equal to the number 9 with high accuracy for 21 real substances as predicted from Van-der-Waals equation of state. The relation is suggested to find the critical volume via the ratio of the Boyle temperature to the critical pressure. The formula is suggested also to define the critical volume via the critical temperature and the parameters of the linear line of unite compressibility.