Final answer:
In an extraction procedure, carboxylic acids like benzoic acid or toluic acid will be found in the aqueous layer due to their polar carboxylic acid group that is soluble in water. Deprotonation increases solubility, but even without it, shorter-chain carboxylic acids can dissolve due to hydrogen bonding.
Step-by-step explanation:
When performing an extraction procedure with a carboxylic acid such as benzoic acid or toluic acid in a mixture of water and organic solvent like diethyl ether, the carboxylic acid will predominantly be found in the aqueous layer. This is due to the polar carboxylic acid group present in these compounds, which forms strong hydrogen bonds with water, making them soluble in water. Carboxylic acids like benzoic acid have a polar group that is water-soluble, albeit less so than fully ionic compounds like LiCl, and a nonpolar aromatic ring that is less favorable to water solubility.
Therefore, in the presence of a base, the carboxylic acid can be deprotonated to form a carboxylate ion, which is even more water-soluble. However, without deprotonation, carboxylic acids with shorter carbon chains are already somewhat soluble in water due to their ability to form hydrogen bonds, as opposed to longer-chain carboxylic acids, which are generally more soluble in organic solvents due to their increased nonpolar character.