Question

The compounds below are to be separated by extraction. A student dissolves the compounds in either and then transfers the solution to a separatory funnel. The student then adds NaOH to the separatory funnel. Describe the separation problem created by this addition. Suggest an action the student can take to successfully continue the separation without starting over. H3c0- -CO2H H3c0- -CO2H ОСН3

Answer 1

1) Separate the aqueous layer from the organic layer using the separation funnel.

2) Treat the aqueous layer to obtain compound A.

3) Distilated the organic layer to obtain compound B.

Step-by-step explanation:

When NaOH is added to the mixture the acid groups will react to produce a salt and increases the polarity of the compounds due to the net charges generated. (Figure 1).

Therefore, the salt produced by compound A will move to the aqueosus layer. Compound B dont react due to the lack of acid groups. So, this molecule will stay in the organic layer.

When the aqueous layer is separated from the organic layer using the separation funnel we will have a separation. The compound will remain in the aqueous layer and compound b will remain in the organic layer.

Then we aqueous layer can be treated with HCl in order to obtain the initial A molecule, in other words: Undo the ionic form of compound A.

The organic layer can be removed by distillation in order to obtain the pure form of compound B.