“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_______________?

Related Mcqs:

1. 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)

2. A solid metallic block weighing 5 kg has an initial temperature of 500°C. 40 kg of water initially at 25°C is contained in a perfectly insulated tank. The metallic block is brought into contact with water. Both of them come to equilibrium. Specific heat of block material is 0.4 kJ.kg-1. K-1. Ignoring the effect of expansion and contraction and also the heat capacity to tank, the total entropy change in kJ.kg-1, K-1 is_________________?

   A. -1.87
   B. 0
   C. 1.26
   D. 3.91

3. Two substances are in equilibrium in a reversible chemical reaction. If the concentration of each substance is doubled, then the value of the equilibrium constant will be___________________?

   A. Same
   B. Doubled
   C. Halved
   D. One fourth of its original value

4. Gibbs free energy of a pure fluid approaches _____________ as the pressure tends to zero at constant temperature?

   A. Infinity
   B. Minus infinity
   C. Zero
   D. None of these

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

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

6. Saturated solution of benzene in water is in equilibrium with a mixture of air and vapours of benzene and water at room temperature and pressure. Mole fraction of benzene in liquid is xB and the vapour pressures of benzene and water at these conditions are pv B and pv w respectively. The partial pressure of benzene in air-vapour mixture is_________________?

   A. PvB
   B. xB.PvB
   C. (Patm – Pvw)xB
   D. xB.Patm

7. 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

8. The equation, (d loge PA/d loge xA) = (d loge PA/d loge xB) applicable to a binary solution of components. A and B in equilibrium with their vapors at constant temperature and pressure is called the _____________ equation?

   A. Van Laar
   B. Margules
   C. Gibbs-Duhem
   D. Gibbs-Duhem-Margules

9. A gas at 0°C was subjected to constant pressure cooling until its volume became half the original volume. The temperature of the gas at this stage will be________________?

   A. 0°C
   B. 0°K
   C. -136.5°C
   D. -136.5°K

10. The quantitative effect of temperature on chemical equilibrium is given by the____________________?

    A. Van’t-Hoff equation
    B. Le-Chatelier’s principle
    C. Arrhenius equation
    D. None of these