If the solubilities of different components (in a liquid-liquid extraction system) increase with rise in temperature, then the temperature above which they dissolve completely is known as the critical solution temperature (CST or consolute temperature). If solubilities increase with decrease in temperature, then CST is the temperature below which they dissolve completely. If a binary system has no critical solution temperature, it implies that___________________?

Related Mcqs:

1. In a liquid-liquid extraction, 10 kg of a solution containing 2 kg of solute C and 8 kg of solvent A is brought into contact with 10 kg of solvent B. Solvent A and B are completely immiscible in each other whereas solute C is soluble in both the solvents. The extraction process attains equilibrium. The equilibrium relationship between the two phases is Y* = 0.9X, where Y* is the kg of C/kg of B and X is kg of C/kg of A. Choose the correct answer?

   A. The entire amount of C is transferred to solvent B
   B. Less than 2 kg but more than 1 kg of C is transferred to solvent B
   C. Less than 1 kg of C is transferred to B
   D. No amount of C is transferred to B

2. Compound A is extracted from a solution of A + B into a pure solvent S. A Co-current unit is used for the liquid-liquid extraction. The inlet rate of the solution containing A is 200 moles of B/hr.m2 and the solvent flow, rate is 400 moles of S/m2. hr. The equilibrium data is represented by Y = 3X2 , where Y is in moles of a A/moles of B and X is in moles A/moles of S. The maximum percentage extraction achieved in the unit is_________________________?

   A. 25%
   B. 50%
   C. 70%
   D. 90%

3. Solvent extraction is the terminology applied to the liquid-liquid extraction, which is preferred for the separation of the components of liquids, when____________________?

   A. Extracting solvent is cheaply & abundantly available
   B. One of the liquid components is heat sensitive
   C. Viscosity of liquid components is very high
   D. One of the liquid components has very high affinity towards the solvent

4. With increase in temperature, the rate of extraction in leaching (solid-liquid extraction system) ?

   A. Increases
   B. Decreases
   C. Remain unaffected
   D. Increases Linearly

5. In a distillation operation, what is the effect of the temperature of the reflux stream (given below) on the condenser and reboiler loads? Reflux conditions: (i) Reflux stream is completely liquid and is at its bubble point. (ii) Reflux stream is below its bubble point ?

   A. Condenser and reboiler loads are the same in both the cases
   B. Reboiler load is the same in both the cases but condenser load is higher in case (ii)
   C. Condenser load is the same in both the cases but reboiler load is higher in case (ii)
   D. Both condenser and reboiler loads are higher in case (ii) as compared to case (i)

6. Experiments were conducted to determine the flux of a species A in a stagnant medium across a gas-liquid interface. The overall mass transfer co-efficient based on the liquid side for dilute systems for the above was estimated to be 4 × 10-3 kg mole/m2.s. The equilibrium data for the system is given as y = 2x. The flux across the interface (in kg mole/m2 .s) for bulk concentrations of A in gas phase and liquid phase as y = 0.4 and x = 0.01 respectively is _________________________?

   A. 5.6 × 10-4
   B. 8.5 × 10-4
   C. 5.6 × 10-3
   D. 8.5 × 10-3

7. The boiling points of pure components of a binary system ________________ with increase in total pressure of the system ?

   A. Decreases
   B. Increases
   C. Remains unchanged
   D. May increase or decrease, depends on the system

8. In case of binary distillation, increasing the reflux ratio above optimum does not result in the increase of_______________________?

   A. Area between operating line and 45° diagonal x-y diagram
   B. Condenser and reboiler surfaces
   C. Tower cross-section
   D. None of these

9. In case of liquid-liquid binary diffusion, diffusivity of one constituent into another is not dependent on the__________________?

   A. Temperature and pressure
   B. Concentration
   C. Nature of the constituents
   D. None of these

10. A coalescer in a mixer-settler liquid-liquid extraction column______________________?

    A. Comprises of thin bed of substances of extended surface having high porosity
    B. Helps in increasing the bubble size entering the settler
    C. Helps in increasing the settling rate of the bubbles
    D. All ‘a’, ‘b’, & ‘c’