Can You Answer Following Questions on Liquid Liquid Extraction Theory Flashcards

How well can do you know about Liquid Liquid Extraction Theory? Answer these quiz based flashcards based on the Liquid Liquid Extraction Theory Questions and check your knowledge. Learn everything related to the Liquid Liquid Extraction Theory with the help of our flashcards quizzes with ease. ​

42 cards   |   Total Attempts: 186
  

Cards In This Set

Front Back
What is liquid liquid extraction?
A widely used method to separate mixtures (mixture can be solid or liquids)
What is liquid liquid extraction based upon?
It is based on the differences in solubility of the components in two immiscible solvents
When choosing the solvents for liquid-liquid extractions, what characteristics must they have?
1) First solvent would preferably completely dissolve both compounds in the mixture
When choosing the solvents for liquid-liquid extractions, what characteristics must they have?
2) Second solvent selected must be immiscible with the first solvent
When choosing the solvents for liquid-liquid extractions, what characteristics must they have?
3) Second solvent should preferentially dissolve only one component of the original mixture
How does liquid liquid extraction work?
Mixture is dissolved or suspended in the first solvent and then this solution is introduced to the second solvent.
How does liquid liquid extraction work?
By shaking the solvent together in an apparatus called a separatory funnel, one component of the mixture will be transferred into the second solvent
How does liquid liquid extraction work?
This would leave the other component in the first solvent.
How does liquid liquid extraction work?
Final separation of two solvents is accomplished using separatory funnel - followed by evaporation of solvents, produces the separated components
But if all we did was the following procedure, we would not have totally separated the two compounds. How do we increase our success?
Compound that we are extracting with 2nd solvent, even though is more soluble in 2nd solvent than 1st but can still dissolve in 1st solvent
What is the extent of the compound dissolve in the less soluble 1st solvent governed by?
The partition coefficient of extraction. This forces us to repeat the extraction step many times
What happens when we repeat the extracting step many times?
We add a fresh portion of the solvent to separatory funnel containing original solution of mixture, to ensure that we get best possible separation
Draw the diagram for successive extractions
Now compare to the one in the manual
Solutions should never occupy more than what amount of volume of the separatory funnel?
Solutions should never occupy more than 2/3 of the volume of the funnel or else proper mixture will be difficult
What do we rest the stopper of the funnel before use?
On a clean watch glass