Which of the following equations is used for the prediction of activity co-efficient from experiments ?

Related Mcqs:

1. 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

2. Joule-Thomson co-efficient which is defined as, η = (∂T/∂P)H = 1/Cp (∂H/∂T)P, changes sign at a temperature known as inversion temperature. The value of Joule-Thomson co-efficient at inversion temperature is ___________________?

   A. 0
   B. ∞
   C. +ve
   D. -ve

3. 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

4. Activity co-efficient is a measure of the____________________?

   A. Departure from ideal solution behaviour
   B. Departure of gas phase from ideal gas law
   C. Vapour pressure of liquid
   D. None of these

5. ______________ Equation predicts the activity co-efficient from experimental data ?

   A. Lewis-Randall
   B. Margules
   C. Van Laar
   D. Both B. & C.

6. For an ideal gas, the activity co-efficient is_________________?

   A. Directly proportional to pressure
   B. Inversely proportional to pressure
   C. Unity at all pressures
   D. None of these

7. In a homogeneous solution, the activity co-efficient of a component depends upon the_________________?

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

8. 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

9. For an ideal solution, the value of activity co-efficient is______________________?

   A. 0
   B. 1
   C. 1

10. What is the value of ln y (where y = activity co-efficient) for ideal gases ?

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