The process employing desorption of the absorbed solute by a solvent is called____________________?

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. Though, theoretically the adsorption & desorption isotherms is expected to coincide but sometimes at least a part of the isotherms does not coincide and this phenomenon is known as adsorption hysteresis. In such cases, the desorption equilibrium pressure is ______________ that obtained for adsorption?

   A. Lower than
   B. Higher than
   C. Same as
   D. Either same or higher than

3. In a single stage extraction process, 10 kg of pure solvent S (containing no solute A) is mixed with 30 kg of feed F containing A at a mass fraction xf = 0.2. The mixture splits into an extract phase E and a raffinate phase R containing A at xB = 0.5 and xR = 0.05 respectively. The total mass of the extract phase is (in Kg) ?

   A. 6.89
   B. 8.89
   C. 10
   D. 8.25

4. Molality is defined as the number of gm moles of solute per _________________ of solvent ?

   A. Litre
   B. gm
   C. Kg
   D. m3

5. The individual mass transfer co-efficients (moles/m2s) for absorption of a solute from a gas mixture into a liquid solvent are, KL = 4.5 and KG = 1.5. The slope of the equilibrium line is 3. Which of the following resistance (s) is (are) controlling ?

   A. Liquid side
   B. Gas side
   C. Interfacial
   D. Both liquid and gas side

6. The individual mass transfer co-efficients (moles/m2s) for absorption of a solute from a gas mixture into a liquid solvent are, KL = 4.5 and KG = 1.5. The slope of the equilibrium line is 3. Which of the following resistance (s) is (are) controlling ?

   A. Liquid side
   B. Gas side
   C. Interfacial
   D. Both liquid and gas side

7. When the solvent dissolves very little of solute, then__________________________?

   A. Solvent of low latent heat of vaporisation should be used
   B. Solvent of low freezing point should be used
   C. Large quantity of solvent is required to extract the solute
   D. Very small quantity of solvent is required

8. Molarity is defined as the number of gm moles of solute per ________________ of solvent?

   A. Litre
   B. kg
   C. gm
   D. c.c

9. In a solution containing 0.30 Kg mole of solute and 600 kg of solvent, the molality is_______________________?

   A. 0.50
   B. 0.60
   C. 1
   D. 2

10. On addition of solute in the solvent, the ______________ of the solution decreases ?

    A. Boiling point
    B. Freezing point
    C. Vapour pressure
    D. Both B. and C.