An open vessel containing 0.205 lbm of liquid water is placed in an empty room 5 ft wide, 4 ft deep, and 7 ft high, which initially contains dry air at 90°F. All the water evaporates without changing the room temperature.

(a) Use the psychrometric chart to estimate the final relative humidity, wet-bulb temperature, humid volume, dew-point temperature, and specific enthalpy of the roomair. Take themolecular weight of dry air to be 29.0, and for simplicity, assume the mass of dry air in the room stays constant at its initial value.

(b) To answer Part (a), you had to make a significant assumption besides the one given in the problem statement. What was it? You could test it by measuring the calculated quantities in different parts of the room.