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Please help me with Organic Lab Post Lab question: Extraction based on acid and base reaction
Here's an interesting paradox. Take a solution of benzoic acid in ether, and add an equal volume of water. The partition coefficient is about 100, i.e., benzoic acid is 100 times more soluble in ether than in water. So only about 1% of the benzoic acid goes into the water. Now use aqueous NaOH or aqueous NaHCO3 instead of plain water. The benzoic acid gets deprotonated, and it all goes into the aqueous layer. Why doesn't only the 1% that partitions into the water get deprotonated? It's not deprotonated in the organic layer, so shouldn't the large partition coefficient keep most of it in the ether? Something must be wrong with this reasoning --- what is it?
Here's an interesting paradox. Take a solution of benzoic acid in ether, and add an equal volume of water. The partition coefficient is about 100, i.e., benzoic acid is 100 times more soluble in ether than in water. So only about 1% of the benzoic acid goes into the water. Now use aqueous NaOH or aqueous NaHCO3 instead of plain water. The benzoic acid gets deprotonated, and it all goes into the aqueous layer. Why doesn't only the 1% that partitions into the water get deprotonated? It's not deprotonated in the organic layer, so shouldn't the large partition coefficient keep most of it in the ether? Something must be wrong with this reasoning --- what is it?
