The concentration of water vapour in troposphere, which depends upon the altitude & temperature, varies in the range of zero to ______________ percent?

Related Mcqs:

1. There are five concentric layers within the atmosphere which is differentiated on the basis of temperature. The atmospheric layer which lies close to the earth’s surface in which human being along with other organisms live is called troposphere. The rate at which air temperature in the troposphere gradually decreases with height is about _____________ °C/km?

   A. 0.05
   B. 1
   C. 6.5
   D. 15

2. Saturated solution of benzene in water is in equilibrium with a mixture of air and vapours of benzene and water at room temperature and pressure. Mole fraction of benzene in liquid is xB and the vapour pressures of benzene and water at these conditions are pv B and pv w respectively. The partial pressure of benzene in air-vapour mixture is_________________?

   A. PvB
   B. xB.PvB
   C. (Patm – Pvw)xB
   D. xB.Patm

3. The vapour pressure of water is given by, in Psat = A – (5000/T), where A is a constant, Psat is the vapour pressure in atm. and T is the temperature in K. The vapor pressure of water in atm. at 50°C is approximately__________________?

   A. 0.07
   B. 0.09
   C. 0.11
   D. 0.13

4. For water at 300°C, it has a vapour pressure 8592.7 kPa and fugacity 6738.9 kPa Under these conditions, one mole of water in liquid phase has a volume of 25.28 cm3 and that in vapour phase in 391.1 cm3.Fugacity of water (in kPa) at 9000 kPa will be__________________?

   A. 6738.9
   B. 6753.5
   C. 7058.3
   D. 9000

5. In troposphere (the weather domain), the temperature ‘t’ at height ‘h’ above the spa level in metres is given by (where, temperature at sea level is 15°C and t is in °C ?

   A. t = 15 – 0.0065h
   B. t = 15 + 0.0065h
   C. t = 0.0035h -15
   D. t = 15 – 0.0035h

6. Vapour which is at a pressure smaller than the saturation pressure for the temperature involved is called a _____________ vapour?

   A. Superheated
   B. Desuperheated
   C. Non-condensable
   D. None of these

7. The wet bulb temperature is lower in dry air than in wet air at the same temperature. A dry bulb thermometer registers a higher temperature than a wet bulb thermometer except at ______________ percent relative humidity ?

   A. 0
   B. 100
   C. 50
   D. None of these

8. At 60° C, vapour pressure of methanol and water are 84.562 kPa and 19.953 kPa respectively. An aqueous solution of methanol at 60° C exerts a pressure of 39.223 kPa; the liquid phase and vapour phase mole fractions of methanol are 0.1686 and 0.5714 respectively. Activity co-efficient of methanol is__________________?

   A. 1.572
   B. 1.9398
   C. 3.389
   D. 4.238

9. Presence of nitrogen in high concentration in contaminated air reduces partial pressure of oxygen in lungs, thereby causing asphyxia (suffocation) leading to death from oxygen deficiency. Concentration of N2 in contaminated air at which it acts as a natural asphyxiate is ≥ _____________ percent?

   A. 84
   B. 88
   C. 80
   D. 92

10. “At the absolute zero temperature, the entropy of every perfectly crystalline substance becomes zero”. This follows from the __________________?

    A. Third law of thermodynamics
    B. Second law of thermodynamics
    C. Nernst heat theorem
    D. Maxwell’s relations