Superheated water vapor enters a well-insulated throttling valve at p1 = 1 atm and t1 = 600°F . At the valve exit, an engineer reports that the exit state is superheated vapor and the thermometer reads t2= 800°F. Assume the effects of kinetic and potential energy are negligible.
a) Determine the entropy production in the valve, in Btu/lb·°R.
b) Can the reported information at the valve exit be possible?