Question

I am writing a c code and using case switch statement for the gas type to give me variables a and b in my equation for pressure. I am confused on how to use user defined function that it is asking for in the bullet points

Answer 1

#include<stdio.h>

void print_list(void){

   printf("%15s%15s%15s%15ds\n", "GasType","Gas","a(L^2-atm/mol^2)", "b(L/mol)");
   printf("%15s%15s%15s%15ds\n", "1","Heleium,He","0.0341", "0.0237");
   printf("%15s%15s%15s%15ds\n", "2","Hydrogen,H2","0.244", "0.0266");
   printf("%15s%15s%15s%15ds\n", "3","Oxygen,O2","1.36", "0.0318");
   printf("%15s%15s%15s%15ds\n", "4","Chlorine,Cl2","6.49", "0.0562");
   printf("%15s%15s%15s%15ds\n", "5","Carbon dioxide,CO2","3.59", "0.0427");
}

double presure_cal(int gas_type, double T, double V, double n){
    double a[5];
    double b[5];
    double value;
    a[0] = 0.0341;
    a[1] = 0.244;
    a[2] = 1.36;
    a[3] = 6.49;
    a[4] = 3.59;
    b[0] = 0.0237;
    b[1] = 0.0266;
    b[2] = 0.0318;
    b[3] = 0.0562;
    b[4] = 0.0427;

   
    value = (0.08206 * T)/((V/n)-b[gas_type-1]) - a[gas_type-1]/((V/n)*(V/n));
    return value;
}

int main(){

    char c;
    double a[5];
    double b[5];
    int n;
    double qty;
    double temp;
    double ivol;
    double fvol;
    double incr;

   

   do {
    printf("%-30s %-30s\n","Number","Gas Type");
    printf("%-30s %-30s\n","1","Helium");
    printf("%-30s %-30s\n","2","Hydrogen");
    printf("%-30s %-30s\n","3","Oxygen");
    printf("%-30s %-30s\n","4","Chlorine");
    printf("%-30s %-30s\n","5","Carbon dioxide");
       do {
           printf("Enter Gas number(1,2,3,5 or 5)>>");
           scanf("%d",&n);
       } while (n <1 || n >5);
       printf("Enter Quantity of gas (in moles)>>");
       scanf("%lf",&qty);
       printf("Enter temperature (in Kelvin)>>");
       scanf("%lf",&temp);
       printf("Enter initial volume (in liters)>>");
       scanf("%lf",&ivol);
       printf("Enter final volume (in liters)>>");
       scanf("%lf",&fvol);
       printf("Enter volume increment(in liters)>>");
       scanf("%lf",&incr);
       c = getchar();
       printf("%-25s %-25s\n","Volume(liters)","Presure(atm)");
       while (ivol <= fvol+incr){

            printf("%-25lf %-25lf\n",ivol,presure_cal(n,temp,ivol,qty));
            ivol = ivol + incr;
       }
      
       printf("Do you want to continue(y or n)?");
       c= getchar();
   } while (c != 'n');
   
    return 0;
}