#ifndef TPX_HYDROGEN_H
#define TPX_HYDROGEN_H

#include "Sub.h"

namespace tpx {

class hydrogen : public Substance{
public:
	hydrogen(){
          m_name = "hydrogen";
          m_formula = "H2";
        }
        virtual ~hydrogen() {}

	double MolWt();
	double Tcrit();
        double Pcrit();
	double Vcrit();
	double Tmin();
	double Tmax();
	char * name();
	char * formula();

	double Pp();
	double up();
	double sp();
	double Psat();

private:
	double ldens();
	double C(int i, double rt, double rt2);
	double Cprime(int i, double rt, double rt2, double rt3);
	double I(int i, double egrho);
	double H(int i, double egrho);
	double W(int i, double egrho);
    double icv(int i, double x, double xlg);
    };

}

#endif // ! HYDROGEN_H