Diffusion co-efficient generally depends upon the temperature, pressure & the nature of the components of the system. Its dimension is not the same as that of the_________________?

Related Mcqs:

1. If the solubilities of different components (in a liquid-liquid extraction system) increase with rise in temperature, then the temperature above which they dissolve completely is known as the critical solution temperature (CST or consolute temperature). If solubilities increase with decrease in temperature, then CST is the temperature below which they dissolve completely. If a binary system has no critical solution temperature, it implies that___________________?

   A. The system comprises of partially miscible liquids
   B. The system comprises of miscible liquids
   C. The system comprises of an azeotrope
   D. On heating, a vapor phase will appear; while on cooling, a solid phase will appear

2. The relation among various mass transfer co-efficients (M.T.C) for ideal gases is given by (where, Kc & Km are M.T.C. for equimolar counter diffusion with concentration & mole fraction respectively as the driving force. and, Kp= M.T.C. for diffusion of a gas through a stagnant inert gas with pressure as driving force) ?

   A. Kc = Kp = Km
   B. Kc = Kp/RT = Km . RT/P
   C. Kc = Kp . RT = Km . RT/p
   D. None of these

3. Ordinary diffusion process is also called ______________ diffusion?

   A. Pressure
   B. Thermal
   C. Concentration
   D. Forced

4. At a fixed pressure, the humidity depends upon the partial pressure of vapor in the mixture. Humidity of a vapour free gas is ________________ percent.?

   A. 100
   B. 0
   C. 50
   D. Between 0 and 100

5. The diffusion co-efficient in m2/s. of acetic acid in benzene (liquid in liquid) is___________________?

   A. 2.09 × 10-4
   B. 2.09 × 10-5
   C. 2.09 × 10-9
   D. 2.09 × 10-12

6. The rough value of diffusion co-efficient of water vapor into air at 25°C may be about ______________ cm2/sec?

   A. 0.25
   B. 2.5
   C. 1.25
   D. 0.0025

7. Gaseous diffusion co-efficient increases with increase in the_____________________?

   A. Pressure
   B. Temperature
   C. Both A. & B.
   D. Neither A. nor B.

8. 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

9. The vapour pressure exerted by the moisture contained in a wet solid depends upon the____________________?

   A. Nature of the moisture
   B. Temperature
   C. Nature of the solid
   D. All A., B. and C.

10. 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