Free energy change at equilibrium is____________________?

Related Mcqs:

1. “When a system in equilibrium is subjected to a change in temperature, pressure or concentration, the equilibrium is displaced in a direction which tends to undo the effect of the change.” This is called the_______________?

   A. Le-Chatelier principle
   B. Kopp’s rule
   C. Law of corresponding state
   D. Arrhenius hypothesis

2. The free energy change for a chemical reaction is given by (where, K = equilibrium constant)________________?

   A. RT ln K
   B. -RT ln K
   C. -R ln K
   D. T ln K

3. 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.

4. Consider the equilibrium A(g) + B(g) = AB(g). When the partial pressure of A is 10-2 atm, the partial pressure of B is 10-3 atm and the partial pressure of AB is 1 atm, the equilibrium constant ‘K’ is____________________?

   A. 10 atm-1
   B. 105 atm-1
   C. 10 (dimensionless)
   D. 105 (dimensionless)

5. Chemical potential (an intensive property) of a substance is a force that drives the chemical system to equilibrium and is equal to its partial molar properties. The ratio of chemical potential to free energy of a pure substance at constant temperature and pressure is________________?

   A. 0
   B. 1
   C. ∞
   D. None of these

6. 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

7. Gibbs free energy at constant pressure and temperature under equilibrium conditions is___________________?

   A. ∞
   B. 0
   C. Maximum
   D. Minimum

8. At constant temperature and pressure, for one mole of a pure substance, the ratio of the free energy to the chemical potential is____________________?

   A. Zero
   B. One
   C. Infinity
   D. Negative

9. Free energy, fugacity and activity co-efficient are all affected by change in the temperature. The fugacity co-efficient of a gas at constant pressure ______________ with the increase of reduced temperature?

   A. Decreases
   B. Increases
   C. Remains constant
   D. Decreases logarithmically

10. Specific/molar Gibbs free energy for a pure substance does not change during________________?

    A. Sublimation
    B. Vaporisation
    C. Melting
    D. Either A, B. or C.