Aniline hydrochloride, (C₆H₅NH₃)Cl, is a weak acid. (Its conjugate base is the weak base aniline, C₆H₅NH₂.) The acid can be titrated with a strong base such as NaOH.

Assume 50.0 mL of 0.100 M aniline hydrochloride is titrated with 0.185 M NaOH. (Ka for aniline hydrochloride is 2.4 × 10⁻⁵.)
(a) What is the pH of the (C₆H₅NH₃)Cl solution before the titration begins?
(b) What is the pH at the equivalence point?
(c) What is the pH at the halfway point of the titration?
(d) Which indicator in Figure 17.11 could be used to detect the equivalence point?
(e) Calculate the pH of the solution after adding10.0, 20.0, and 30.0 mL of base.
(f) Combine the information in parts (a), (b),(c), and (e), and plot an approximate titration curve.

Data given in figure 17.11

Transcribed Image Text:

C6H5NH₂+ (aq) + OH¯(aq) = CH,NH,(aq) +H,O(l)