Question

1. write a balanced equation for the acid-base reaction that occurs when the benzoic acid was extracted from the ether solution.
A balanced equation for the acid-base reaction required to recover the benzoic acid from the aqueous layer. DRAW STRUCTURES FOR ALL ORG COMPOUNDS. do not use formulas

2. write a balanced equation for the acid-base reaction that occurs when the ethyl-4-aminobenzoate was extracted from the ether solution.
A balanced equation for the acid-base reaction required to recover ethyl-4-aminobenzoate from the aqueous layer. DRAW STRUCTURES FOR ALL ORG COMPOUNDS. do not use formulas

3. Explain how you would use acid base extractions to seperate benzoic acid and p-tert-butylphenol. both of these compounds are acids, but they vary in strength. (benzoic acid pka = 4.17 and p-tertbutylphenyl pka=10.17.

Answer 1

1)

3) There is a great difference between the pKa values of benzoic acid and p-tertbutylphenyl, showing that benzoic acid is stronger acid than p-tertbutylphenol. So we can use acid base extraction for separation of the two acidic compounds.

The mixture can be separated by use of a weak base bicarbonate ion . Bicarboate ion will convert only carboxylic acid into its conjugate base making it soluble in aqueous layer however p-tertbutylphenol will remain insoluble as it will not ionize. We cannot use NaOH, as it will ionize both the compounds.