Partition Coefficient

Question 1

What is solvent extraction?

Answer 1

Solvent extraction can be an application of the partition of a solute between two liquids. It is based on the relative solubility of a compound in two different immiscible liquids, usually water and an organic solvent.

Question 2

Describe the process of solvent extraction.

Answer 2

The two solvents form two separate layers in the separating funnel and an equilibrium exists between the two layers. The lower layer is run off into one container and the upper layer is poured out into another container.

Question 3

What does the quantity of the solute depend on?

Answer 3

The quantity of solute extracted depends on the equilibrium constant and on the number of times that the process is repeated

Question 4

When is the mass of solute extracted greater?

Answer 4

The mass of solute extracted is greater if a number of extractions using smaller volumes of solvent are carried out rather than a single extraction using a large volume of solvent

Question 5

What does the selection of the solvent involve consideration of?

Answer 5

Selection of the solvent should involve consideration of:
miscibility with water 
solubility of the compound 
volatility of the solvent 
reactivity between the compound and solvent