A. Phase change of the solute as it dissolves in the solvent
B. Diffusion of the solute through the solvent in the pores to the outside of the particle
C. Diffusion of the solute from the solution in contact with the particle to the main bulk of the
solution
D. All A , B. & C.
Related Mcqs:
- 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% - With increase in temperature, the rate of extraction in leaching (solid-liquid extraction system) ?
A. Increases
B. Decreases
C. Remain unaffected
D. Increases Linearly - 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 - 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 - A solid is being dried in the linear drying rate regime from moisture content Xo to XF. The drying rate is zero at X = 0 and the critical moisture content is the same as the initial moisture Xo. The drying time for M = (Ls/ARc) is (where, L = total mass of dry solid, A = total surface area for drying Rc = Constant maximum drying rate per unit area X = moisture content (in mass of water/mass of dry solids)) ?
A. M(Xo – XF)
B. M(Xo/XF)
C. M ln(Xo/XF)
D. MXo ln(Xo/XF) - A solid is being dried in the linear drying rate regime from moisture content Xo to XF. The drying rate is zero at X = 0 and the critical moisture content is the same as the initial moisture Xo. The drying time for M = (Ls/ARc) is (where, L = total mass of dry solid, A = total surface area for drying Rc = Constant maximum drying rate per unit area X = moisture content (in mass of water/mass of dry solids))_____________?
A. M(Xo – XF)
B. M(Xo/XF)
C. M ln(Xo/XF)
D. MXo ln(Xo/XF) - It takes 6 hours to dry a wet solid from 50% moisture content to the critical moisture content of 15%. How much longer it will take to dry the solid to 10% moisture content, under the same drying conditions? (The equilibrium moisture content of the solid is 5%) ?
A. 15 min
B. 51 min
C. 71 min
D. 94 min - In liquid-liquid extraction, the number of phases at plait point is __________________?
A. 1
B. 2
C. 3
D. 4 - Which of the following equipments is not used in liquid-liquid extraction ?
A. Pachuka tank
B. Agitated vessels
C. Centrifugal extractors
D. Packed towers - 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___________________?
A. The system comprises of partially miscible liquids
B. The system comprises of miscible liquids
C. The system comprises of an azeotrope
D. On heating, a vapor phase will appear; while on cooling, a solid phase will appear
