Problem 1: A sealed rigid tank contains 1 kg of wet steam at 300 °C. The fraction of the liquid in the tank is not known. Upon adding heat to the tank it is observed that the vapor condenses. The heating stops when the system becomes saturated liquid. At that point the pressure in the tank is 148 bar.
a) What fraction of the water is initially liquid?
b) How much heat was added?
c) What is the minimum amount of liquid that must be present in the tank initially, in order to observe condensation upon heating?
d) What would be observed upon heating, if the initial amount of liquid was less than the minimum value calculated in part (c)?
e) How do you explain the fact that heating can result in condensation of the vapor?