A laboratory mixture consists of an organic solute dissolved in water. A chemist decides to isolate the organic solute by solvent extraction using ethoxyethane (diethyl ether). Arrange the following procedural steps in the correct logical sequence from first to last to complete this separation using a separating funnel.
- 1Close the stopcock of the separating funnel, add the aqueous mixture, and pour in the ethoxyethane solvent.
- 2Insert the stopper, invert the funnel, and open the stopcock periodically to vent built-up solvent vapor pressure.
- 3Mount the funnel vertically in a ring stand and allow the liquid mixture to stand undisturbed until two distinct layers separate.
- 4Remove the stopper, open the stopcock to run off the denser bottom aqueous layer, and then collect the upper ethoxyethane layer separately.
Answer
The correct logical sequence is: first, close the stopcock and introduce the aqueous mixture and ethoxyethane into the funnel; second, stopper, invert, shake, and periodically vent internal pressure; third, mount the funnel on a stand and allow the immiscible layers to settle completely; fourth, remove the stopper and carefully drain the lower aqueous layer followed by collecting the upper organic layer.
The correct procedural order follows standard chemical laboratory protocol: loading reagents, mixing/partitioning with pressure venting, phase settling via density separation, and step-by-step draining under atmospheric pressure.
Step-by-Step Solution
Key Concept
Solvent Extraction and Separating Funnel Manipulation