Chapter 5 : Equations of state

Example 5.1 pageno : 167

In [1]:
# Variables
t = 304;			#temperature of the gas in k
p = 73;			#pressure of the gas in atm
r = 0.00366;			#universal gas constant in j/K/mole
			#ct = 8a/27br;cp = a/27b**2

# Calculations
b = (t*r/(8*p));
a = p*27*b**2;

# Result
print 'the value of the constant b is %.5f  \
\nthe value of the constant a is %3.5f'%(b,a)

the value of the constant b is 0.00191  
the value of the constant a is 0.00715

Example 5.4 pageno : 169

In [5]:
# Variables
tc = 132;			#critical temperature in K
pc = 37.2;			#critical pressure in atm
r = 82.07;			#universal gas constant in cm**3atm/mole/K

# Calculations
a = 27*(r**2)*(tc**2)/(64*pc);			#value of a in atm/cm**6/mol**2
b = r*tc/(8*pc);			#value of b in cm**3/mol

# Result
print 'the value of is %.2e atm/cm**6/mol**2  \
\nthe value of b is %3.2f cm**3/mol'%(a,b)

the value of is 1.33e+06 atm/cm**6/mol**2  
the value of b is 36.40 cm**3/mol

Example 5.5 pageno : 169

In [6]:
# Variables
p = 2.26*1.013*10**5;			#critical pressure in N/m**2
v = 4./69;			#critical volume in m**3/kmol
r = 8.31*10**3;			#universal gas consmath.tant in J/kmol.K

# Calculations
t = (8*p*v/(3*r));			#critical temperature in K

# Result
print 'critical temperature of the given problem is %3.2f K'%(t)

critical temperature of the given problem is 4.26 K