Gibbs phase rule finds application, when heat transfer occurs by___________________?

Related Mcqs:

1. 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

2. Gibbs free energy (G) is represented by, G = H – TS, whereas Helmholtz free energy, A. is given by, A = E – TS. Which of the following is the Gibbs-Helmholtz equation ?

   A. [∂(G/T)/∂T] = – (H/T2)
   B. [∂(A/T)/∂T]V = – E/T2
   C. Both A. and B.
   D. Neither A. nor B.

3. Gibbs-Duhem equation relates composition in liquid phase and the _____________ at constant temperature & pressure?

   A. Fugacity
   B. Partial pressure
   C. Activity co-efficient
   D. All (A), (B), and (C)

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. The following heat engine produces power of 100,000 kW. The heat engine operates between 800 K and 300 K. It has a thermal efficiency equal to 50% of that of the Carnot engine for the same temperature. The rate at which heat is absorbed from the hot reservoir is____________________?

   A. 100,000 kW
   B. 160,000 kW
   C. 200,000 kW
   D. 320,000 kW

6. The molar excess Gibbs free energy, gE, for a binary liquid mixture at T and P is given by, (gE/RT) = A . x1. x2, where A is a constant. The corresponding equation for ln y1, where y1 is the activity co-efficient of component 1, is__________________?

   A. A . x22
   B. Ax1
   C. Ax2
   D. Ax12

7. The standard Gibbs free energy change of a reaction depends on the equilibrium______________________?

   A. Pressure
   B. Temperature
   C. Composition
   D. All A, B. and C

8. Gibbs free energy of mixing at constant pressure and temperature is always__________________?

   A. 0
   B. ∞
   C. + ve
   D. – ve

9. Gibbs free energy per mole for a pure substance is equal to the__________________?

   A. Latent heat of vaporisation
   B. Chemical potential
   C. Molal boiling point
   D. Heat capacity

10. The change in Gibbs free energy for vaporisation of a pure substance is___________________?

    A. Positive
    B. Negative
    C. Zero
    D. May be positive or negative