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

Related Mcqs:

1. 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

2. A liquid under pressure greater than its vapour pressure for the temperature involved is called a _____________ liquid?

   A. Sub-cooled
   B. Saturated
   C. Non-solidifiable
   D. None of these

3. 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

4. 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

5. Percentage saturation of a vapor bearing gas is always _____________ the relative saturation?

   A. Higher than
   B. Smaller than
   C. Equal to
   D. Either A. or B.; depends on the system

6. 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

7. Air at a temperature of 20°C and 750 mm Hg pressure has a relative humidity of 80%. What is its percentage humidity? Vapour pressure of water at 20°C is 17.5 mm Hg?

   A. 80.38
   B. 80
   C. 79.62
   D. 78.51

8. When liquid and vapour phases of one component system are in equilibrium (at a given temperature and pressure), the molar free energy is__________________?

   A. More in vapour phase
   B. More in liquid phase
   C. Same in both the phases
   D. Replaced by chemical potential which is more in vapour phase

9. When liquid and vapour phase of multi-component system are in equilibrium (at a given temperature and pressure), then chemical potential of each component is___________________?

   A. Same in both the phases
   B. Zero in both the phases
   C. More in vapour phase
   D. More in liquid phase

10. The effect of changing the evaporator temperature on COP as compared to that of changing the condenser temperature (in vapour compression refrigeration system) is__________________?

    A. Less pronounced
    B. More pronounced
    C. Equal
    D. Data insufficient, can’t be predicted