A mixture of 10% C6H6 vapour in air at 25°C and 750 mm Hg has a dew point of 20°C. Its dew point at 30°C and 700 mm Hg will be around _______________ °C?

Related Mcqs:

1. An air-water vapour mixture has a dry bulb temperature of 60°C and a dew point temperature of 40°C. The total pressure is 101.3 kPa and the vapour pressure of water at 40°C and 60°C are 7.30 kPa and 19.91 kPa respectively. The humidity of air sample expressed as kg of water vapour/kg of dry air is__________________?

   A. 0.048
   B. 0.079
   C. 0.122
   D. 0.152

2. Condensation of a vapour-gas mixture just begins, when (where, p = partial pressure of the vapour P = vapour pressure of the liquid) ?

   A. p = P
   B. p >>P
   C. p < P
   D. p << P

3. At equilibrium the concentration of water in vapour phase (C*) in kg/m3 of air space and the amount of water (m) adsorbed per kg of dry silica gel are related by, C* = 0.0667m. To maintain dry conditions in a room of air space 100m3 containing 2.2 kg of water vapour initially, 10 kg of dry silica gel is kept in the room. The fraction of initial water remaining in the air space after a long time (during which the temperature is maintained constant) is_________________?

   A. 0.0
   B. 0.2
   C. 0.4
   D. 1.0

4. The dew point of an unsaturated gas-vapor mixture does not depend upon the _________________ of the mixture?

   A. Composition
   B. Temperature
   C. Total pressure
   D. All A, B. and C.

5. The dew point of an unsaturated gas-vapor mixture does not depend upon the ____________________ of the mixture?

   A. Composition
   B. Temperature
   C. Total pressure
   D. All A., B. and C.

6. With increase in absolute humidity, the dew point of an unsaturated mixture of air and water vapor (at constant pressure and temperature) ?

   A. Increases
   B. Remains unchanged
   C. Decreases
   D. Decreases linearly

7. The wet and ‘dry bulb temperature for a vapour-gas mixture are 25°C and 30°C respectively. If the mixture is heated to 45°C at constant pressure, the wet bulb temperature will be ______________ °C ?

   A. 25
   B. > 25
   C. < 25
   D. – 25

8. The wet and ‘dry bulb temperature for a vapour-gas mixture are 25°C and 30°C respectively. If the mixture is heated to 45°C at constant pressure, the wet bulb temperature will be ______________ °C?

   A. 25
   B. > 25
   C. < 25
   D. – 25

9. The relative saturation of a partially saturated mixture of vapour and gas can be increased by ________________ of the mixture?

   A. Reducing the total pressure
   B. Increasing the total pressure
   C. Reducing the temperature
   D. Both B. and C.

10. Unsaturated air (with dry bulb temperature and dew point being 35°C and 18°C respectively) is passed through a water spray chamber maintained at 15°C. The air will be cooled_________________?

    A. And humidified
    B. And dehumidified with increase in wet bulb temperature
    C. At the same relative humidity
    D. And dehumidified with decrease in wet bulb temperature