# Gas pressure from SRK equation of state
# Verified Solution: P = 96.129, z = 0.253814

P = R*T/(V-b)-alpha*a/(V*(V+b)) # Pressure (atm)
a = 0.42747*R^2*Tc^2/Pc #SRK constant
b = 0.08664*R*Tc/Pc #SRK constant
alpha = (1+m*(1-sqrt(T/Tc)))^2 #SRK constant alpha
m = 0.48508+1.55171*omega-0.1561*omega^2 #SRK constant m
Tc = 304.2 #Critical temperature (K)
Pc = 72.9 #Critical pressure (atm)
R = 0.08206 #Gas constant (L-atm/gmol-K)
omega = 0.225 #Acentric factor
T = 300 #Temperature (K)
V=0.065 # Volume (L/g-mol)
Tr=T/Tc
Pr=P/Pc
z=P*V/(R*T)

Explicit Equations Preview

P = \frac{R \cdot T}{V - b} - \frac{α \cdot a}{V \cdot (V + b)}

a = \frac{0.42747 \cdot R^{2} \cdot {Tc}^{2}}{Pc}

b = \frac{0.08664 \cdot R \cdot Tc}{Pc}

α = {(1 + m \cdot (1 - \sqrt{\frac{T}{Tc}}))}^{2}

m = 0.48508 + 1.55171 \cdot ω - 0.1561 \cdot ω^{2}

Tc = 304.2

Pc = 72.9

R = 0.08206

ω = 0.225

T = 300

V = 0.065

Tr = \frac{T}{Tc}

Pr = \frac{P}{Pc}

z = \frac{P \cdot V}{R \cdot T}

Program validated. Ready to Solve.

Explicit Equations Solution

	Variable	Value	Details
1	Tc	304.2
2	Pc	72.9
3	R	0.08206
4	a	3.6539244	a = 0.42747R^2Tc^2/Pc
5	b	0.029667547	b = 0.08664RTc/Pc
6	omega	0.225
7	m	0.82631219	m = 0.48508+1.55171omega-0.1561omega^2
8	T	300
9	alpha	1.0114811	alpha = (1+m*(1-sqrt(T/Tc)))^2
10	V	0.065
11	P	96.128994	P = RT/(V-b)-alphaa/(V*(V+b))
12	Tr	0.98619329	Tr = T/Tc
13	Pr	1.3186419	Pr = P/Pc
14	z	0.25381366	z = PV/(RT)

Settings and Hints

	Name/Source	Value	Type
1	Explicit equations	14	Setting
2	Anonymous expressions	0	Setting
3	#@report_fix_digits = 8		Default (integer)
4	#@report_show_source = true		Default (boolean)
5	#@report_show_header = false		Default (boolean)
6	#@report_show_settings = true		Default (boolean)

Messages

	Severity	Description
1	Info	-Infor- Explicit variables (14) P, a, b, alpha, m, Tc, Pc, R, omega, T, V, Tr, Pr, z
2	Info	-Infor- All variables (14) R, T, V, b, alpha, a, P, Tc, Pc, m, omega, Tr, Pr, z

Explicit Equations Solution

Settings and Hints

Messages

Source