Problem 1. Consider 100 m^3 of moist air at 100 kPa , 45 C and 80 % , R.H.
Part A
Calculate the humidity ratio (ω).
Express the answer in kilograms of water per kilograms of dry air to four significant figures.
Part B
Calculate the dew point.
Express your answer in degrees Celsius to four significant figures.
Part C
Calculate the mass of vapor.
Express your answer to three significant figures using appropriate units.
Part D
What-if scenario: What would the dew point be if the moist air was at 60 % R.H.?
Express your answer in degrees Celsius to four significant figures.
Problem 2. A room contains air at 10 °C and 95 kPa with a relative humidity of 80 %
Part A
Determine the partial pressure of dry air.
Express your answer to four significant figures using the appropriate units.
Part B
Determine the specific humidity (ω) of the air.
Express your answer in kilograms of water vapor per kilograms of dry air to four significant figures.
Part C
Determine the enthalpy per unit mass of dry air.
Express your answer in kiljoules per kilograms of dry air to four significant figures.
Part D
What-if scenario: Determine the partial pressure of dry air if the pressure is 85 kPa.
Express your answer to four significant figures using the appropriate units.
Part E
What-if scenario: Determine the specific humidity (ω) of the air if the pressure is 85 kPa.
Express your answer in kilograms of water vapor per kilograms of dry air to four significant figures.
Part F
What-if scenario: Determine the enthalpy per unit mass of dry air if the pressure is 85 kPa.
Express your answer in kiljoules per kilograms of dry air to four significant figures.
Problem 3. A tank with a volume 20 m3 contains a mixture of carbon dioxide and water vapor at 18 °C and 100 kPa with a relative humidity (?) of 80 % .
Part A
Determine the partial pressure of dry CO2.
Express your answer to four significant figures using the appropriate units.
Part B
Determine the specific humidity (ω) of the mixture.
Express your answer in kilograms of water per kilograms of carbon dioxide to four significant figures.
Part C
Determine the dew point.
Express your answer in degrees Celsius to four significant figures.
Part D
Determine the amount of vapor.
Express your answer to four significant figures using the appropriate units.
Part E
Determine the mass of CO2.
Express your answer to four significant figures using the appropriate units.
Part F
What-if scenario: What would the amount of vapor be if the mixture was composed of dry air and water vapor?
Express your answer to four significant figures using the appropriate units.
Problem 3. A 10 m3 tank contains saturated air at 40 °C, 101 kPa .
Part A
Determine the specific humidity (ω).
Express your answer in kilograms of water per kilograms of dry air to four significant figures.
Part B
Determine the mass of dry air.
Express your answer to four significant figures using the appropriate units.
Part C
Determine the enthalpy of the dry air, per unit mass of the dry air.
Express your answer in kilojoules per kilograms of dry air to four significant figures.
Problem 4. Air in a room has a dry-bulb temperature of 24 °C and a wet-bulb temperature of 18 °C. Assume a pressure of 100 kPa .
Part A
Determine the specific humidity (ω).
Express your answer to four significant figures.
Part B
Determine the relative humidity (?).
Express your answer to four significant figures.
Part C
Determine the dew-point temperature.
Express your answer to four significant figures.
Part D
What-if scenario: What would the relative humidity be if the wet-bulb temperature was 15°C?
Express your answer to four significant figures.
Problem 5. Air in a room is at 1 atm , 22 °C and 55 % percent relative humidity (?).
Part A
Determine the specific humidity (ω) of the air.
Express your answer in kilograms of water per kilograms of dry air to four significant figures.
Part B
Determine the enthalpy (h) of the air.
Express your answer in kilojoules per kilograms of dry air to four significant figures.
Part C
Determine the wet-bulb temperature of the air.
Express your answer in degrees Celsius to four significant figures.
Part D
Determine the dew-point temperature of the air.
Express your answer in degrees Celsius to four significant figures.
Part E
Determine the specific volume (v) of the air.
Express your answer in cubic meters per kilograms of dry air to four significant figures.
Problem 6. Air in a room has a pressure of 1 atm , a dry-bulb temperature of 26 °C, and a wet-bulb temperature of 16 °C.
Part A
Determine the specific humidity (ω) of the air.
Express your answer in kilograms of water per kilograms of dry air to four significant figures.
Part B
Determine the enthalpy (h) of the air.
Express your answer in kilojoules per kilograms of dry air to four significant figures.
Part C
Determine the relative humidity (?) of the air.
Express your answer in percent to four significant figures.
Part D
Determine the dew-point temperature of the air.
Express your answer in degrees Celsisu to four significant figures.
Part E
Determine the specific volume (v) of the air.
Express your answer in cubic meters per kilograms of dry air to four significant figures.