If the vapour pressure at two temperatures of a solid phase in equilibrium with its liquid phase are known, then the latent heat of fusion can be calculated by the _________________?

Related Mcqs:

1. 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

2. 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

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. A reasonably general expression for vapour-liquid phase equilibrium at low to moderate pressure is φi yi P = Yi xifi° where, Φ is a vapor fugacity component, Yi is the liquid activity coefficient and fi° is the fugacity of the pure component i. the Ki value (Yi = Ki xi) is therefore, in general a function of ______________________?

   A. Temperature only
   B. Temperature and pressure only
   C. Temperature, pressure and liquid composition xi only
   D. Temperature, pressure, liquid composition xi and vapour composition yi

5. 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

6. 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

7. The reaction A (l) → R(g) is allowed to reach equilibrium conditions in an autoclave. At equilibrium, there are two phases, one a pure liquid phase of A and the other a vapor phase of A, R and S. Initially A alone is present. The numbers of degrees of freedom are ?

   A. 1
   B. 2
   C. 3
   D. 0

8. 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

9. A solid is transformed into vapour without going to the liquid phase at_________________?

   A. Triple point
   B. Boiling point
   C. Below triple point
   D. Always

10. “The equilibrium value of the mole fraction of the gas dissolved in a liquid is directly proportional to the partial pressure of that gas above the liquid surface”. This statement pertaining to the solubility of gases in liquid is the ______________ law?

    A. Raoult’s
    B. Henry’s
    C. Amagat’s
    D. None of these