Evaluate the following list of organic compounds: Phenol, Benzyl alcohol, Benzoic acid, 2-Nitropheno — GOC and Organic Chemistry Basics Chemistry Question
Question
Evaluate the following list of organic compounds: Phenol, Benzyl alcohol, Benzoic acid, 2-Nitrophenol, Cyclohexanol, Benzene sulphonic acid, and 1-Butyne. Exactly how many of these explicitly listed compounds are sufficiently acidic to dissolve completely in dilute aqueous sodium hydroxide ($NaOH$)?
💡 Solution & Explanation
To dissolve in $NaOH$, a compound must be a stronger acid than water ($pKa \approx 15.7$) to shift the equilibrium towards the products. Phenol ($pKa \approx 10$), Benzoic acid ($pKa \approx 4.2$), 2-Nitrophenol ($pKa \approx 7.2$), and Benzene sulphonic acid ($pKa \approx 0$) are strong enough to react and dissolve. Alcohols (Benzyl alcohol, Cyclohexanol) and terminal alkynes (1-Butyne) are weaker acids than water and will not dissolve in aqueous $NaOH$.