// (3.1) A closed, rigid container of volume 0.5 m3 is placed on a hot plate. Initially, the container holds a two-phase mixture of saturated liquid water and saturated water vapor at p1 = 1 bar with a quality of 0.5. After heating, the pressure in the container is p2=  1.5 bar. Indicate the initial and final states on a T–v diagram, and determine (a) the temperature, in degree Celcius, at each state.(b) the mass of vapor present at each state, in kg.(c) If heating continues, determine the pressure, in bar, when the container holds only saturated vapor.

// solution 

//initializing variables
p1 = 10^5                    // initial pressure in pascal 
x1 = .5                      // initial quality
p2 = 1.5*10^5                // pressure after heating in pascal
v = .5                       // volume of container in m3

vf1 = 1.0432*10^(-3)         // specific volume of fluid in state 1 in m3/Kg(from table A-3)
vg1 = 1.694                  // specific volume of gas in state 1 in m3/kg(from table A-3)

v1 = vf1 + x1*(vg1-vf1)      // specific volume in state 1 in m3/Kg
v2 = v1                      // specific volume in state 2 in m3/Kg
vf2 = 1.0582*10^(-3)         //  specific volume of fluid in state 2 in m3/Kg(from table A-3)
vg2 = 1.159                  //  specific volume of gas in state 2 in m3/Kg(from table A-3) 

// part (a)
T1 = 99.63                   // temperature in degree celcius in state 1, from table A-3
T2 = 111.4                   // temperature in degree celcius in state 2, from table A-3
printf('the temperature in degree celcius in state 1 is:\n\t T1 = %f',T1);
printf('\nthe temperature in degree celcius in state 2 is:\n\t T2 = %f',T2);

// part (b)
m = v/v1                     // total mass in Kg
mg1 = x1*m                   // mass of vapour in state 1 in Kg
printf('\nthe mass of vapor in state 1 in Kg is:\n\t mg1 = %f',mg1 );
x2 = (v1-vf2)/(vg2-vf2)      // quality in state 2
mg2 = x2*m                   // mass of vapor in state 2 in Kg 
printf('\nthe mass of vapor in state 2 in Kg is:\n\t mg2 = %f',mg2 );

//part(c)
p3 = 2.11                    // pressure in state 3 from table A-3
printf('\nthe pressure corresponding to state 3 in bar is:\n\t p3 = %f',p3 );