$8\mathrm{.}142$ a$.$ Write the equilibrium equation for the acid$-$base reaction that takes place between aniline and water.

b$.$ Being attached to an aromatic ring causes the $-N{H}_2$ group of aniline to be less basic than nonaromatic amines, such as propylamine $($Problem $8\mathrm{.}141).$ Because aniline is a weak base, its conjugate acid is relatively strong $)=(4\mathrm{.}6.$ Which predominates at $pH7,$ aniline or its conjugate acid?