Activity co-efficient is a measure of the____________________?

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. Fugacity is a measure of the____________________?

   A. Escaping tendencies of the same substance in different phases of a system
   B. Relative volatility of a mixture of two miscible liquids
   C. Behaviour of ideal gases
   D. None of these

3. The capacity of a spring to store energy is called the spring form co-efficient. Stiffness of a spring is measured by the____________________?

   A. Ability to absorb shock
   B. Capacity to store energy
   C. Ratio of the wire & coil diameters
   D. Load to produce unit deflection

4. 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

5. 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

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

   A. Van Laar equation
   B. Margules equation
   C. Wilson’s equation
   D. All A, B. and C

7. 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

8. 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)

9. 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

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

    A. 0
    B. 1
    C. 1