Benzoic acid (pKₐ = 4.20) is mixed with an equimolar amount of aniline; the pKₐ of…
CHEMISTRY · Single correct · AP · Chemistry · Acids and Bases · Acids and Bases
Problem
Benzoic acid (pKₐ = 4.20) is mixed with an equimolar amount of aniline; the pKₐ of the conjugate acid of aniline (the anilinium ion) is 4.60. After the mixture reaches equilibrium in water at 25 °C, which pair of species will be present at the highest concentrations?
(a) Benzoate ion and aniline
(b) Benzoate ion and anilinium ion
(c) Benzoic acid and aniline
(d) Only benzoate ion and anilinium ion, because the proton transfer goes to completion