//ques-25.21
//Calculating pressure using van der Waals equation
clc
n=2;//moles of ammonia
T=300;//temperature (in K)
V=5*10^-3;//volume (in kL)
a=0.417;//(in N M^4/mol^2)
b=0.037*10^-3;//(in m^3/mol)
P=(n*8.314*T)/(V-n*b)-(a*n^2)/V^2;
printf("The pressure required is %.1f N/m^2.",P);