A student needs to extract a non-polar organic solute from an aqueous mixture using diethyl ether in a separating funnel. Arrange the following procedural steps in the correct logical sequence from first to last.
- 1Pour the aqueous mixture and diethyl ether into the separating funnel, insert the stopper, and invert the funnel while periodically opening the stopcock to vent pressure.
- 2Clamp the separating funnel vertically in a ring stand and allow the mixture to stand until two distinct liquid layers separate cleanly.
- 3Remove the stopper from the funnel top and open the stopcock to run off the lower, denser aqueous layer into a beaker.
- 4Pour or drain the upper organic layer containing the dissolved solute through the top neck into a separate clean flask.
Answer
The correct sequence of steps is: First, pour the liquids into the funnel, stopper, shake, and periodically vent pressure; second, clamp the funnel and allow the mixture to settle into two clear layers; third, unstopper the funnel and drain the denser lower aqueous layer through the stopcock; fourth, collect the lighter organic layer containing the solute from the funnel.
In solvent extraction using a separating funnel, the mixture and extracting solvent must first be thoroughly shaken together with periodic pressure venting to maximize solute partition into the solvent. The funnel is then supported upright until the immiscible liquids separate into two distinct layers. The top stopper is removed to equalize atmospheric pressure before opening the stopcock to run off the lower (denser) aqueous layer. Finally, the upper (less dense) organic layer containing the solute is collected separately.
Step-by-Step Solution
Key Concept
Procedural execution of liquid-liquid solvent extraction using a separating funnel
Estimated Time:1m 30s