Redlich–Kwong equation of state calculator (V3)

Calculate pressure/volume/temperature, compressibility factor, and fugacity coefficient for liquid/gas/supercritical fluid.

Usage:

Enter the critical temperature and pressure.
Enter two of three quantities leaving blank the field to be calculated.
Select units.
Click Calculate to get the missing quantity, compressibility factor, and fugacity coefficient.
Stability is reported for gas and liquid. Supercritical and unstable phases are referred to as “fluid”.
Simple expressions (e.g., 100+273.15) are accepted in input fields.
Spaces, tabs etc. are not allowed in input fields.
The decimal separator is period(.), not comma(,).

Results:

fluid: n.a.

gas: n.a.

liquid: n.a.

Notation:
T = temperature
P = pressure
Vm = molar volume
Tc = critical temperature
Pc = critical pressure
reduced quantities: Tr=T/Tc, Pr=P/Pc, Vr=Vm/(R*Tc/Pc)
Z = Pr*Vr/Tr= P*Vm/(R*T) = compressibility factor
φ = fugacity coefficient
1 atm = 101 325 Pa, 1 bar = 100 000 Pa

Theory (in Czech) – Critical data of selected gases – Version 1 (with reduced quantites) – Version 2 (no stability detection)

Critical temperature =	Temperature =	°C	K
Critical pressure =	Pressure =	Pa	kPa	bar	atm	MPa
	Molar volume =	m³/mol	dm³/mol	cm³/mol