During the phase transition, _______________ changes?

Related Mcqs:

1. There is a change in ______________ during the phase transition?

   A. Volume
   B. Pressure
   C. Temperature
   D. All a, b & c

2. While dissolving a gas into a liquid at a constant temperature, the ratio of the concentration of the gas in the solution phase and in the gaseous phase is _______________?

   A. Infinity
   B. Unity
   C. Constant
   D. Negative

3. 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

4. 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 _________________?

   A. Maxwell’s equation
   B. Clausius-Clapeyron Equation
   C. Van Laar equation
   D. Nernst Heat Theorem

5. 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

6. 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

7. Number of components (C), phase (P) and degrees of freedom (F) are related by Gibbs phase rule as________________?

   A. P + F – C = 2
   B. C = P – F + 2
   C. F = C – P – 2
   D. P = F – C – 2

8. Specific ____________ does not change during a phase change (e.g. sublimation, melting, vaporisation etc.)?

   A. Entropy
   B. Internal energy
   C. Enthalpy
   D. Gibbs free energy

9. Specific _____________ does not change during phase change at constant temperature and pressure?

   A. Entropy
   B. Gibbs energy
   C. Internal energy
   D. Enthalpy

10. ____________ does not change during phase transformation processes like sublimation, melting & vaporisation?

    A. Entropy
    B. Gibbs free energy
    C. Internal energy
    D. All (A), B. & (C)