1. Calculate the value of the Gibbs function for saturated steam at 500°F as a saturated liquid, saturated vapor, and a mixture of liquid and vapor with a quality of 40 percent. Demonstrate that phase equilibrium exists.
2. An ammonia-water mixture is at 10°C. Determine the pressure of the ammonia vapor when the mole fraction of the ammonia in the liquid is
(a) 20 percent and
(b) 80 percent. The saturation pressure of ammonia at 10°C is 615.3 kPa.