25. Phenols
Phenol Acidity
8PRACTICE PROBLEM
4-chlorobenzoic acid and 4-methoxyphenol are only very slightly soluble in water. The addition of NaHCO3 to the water allows 4-chlorobenzoic acid to fully dissolve, but not 4-methoxyphenol. The addition of NaOH causes both 4-chlorobenzoic acid and 4-methoxyphenol to fully dissolve. Give an approximation for the pKₐ of 4-methoxyphenol. [The pKa of H2CO3 is 6.4.]
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4-chlorobenzoic acid and 4-methoxyphenol are only very slightly soluble in water. The addition of NaHCO3 to the water allows 4-chlorobenzoic acid to fully dissolve, but not 4-methoxyphenol. The addition of NaOH causes both 4-chlorobenzoic acid and 4-methoxyphenol to fully dissolve. Give an approximation for the pKₐ of 4-methoxyphenol. [The pKa of H2CO3 is 6.4.]