B.向\(\rm{Al_{2}}\)\(\rm{(SO}\)\(\rm{{\,\!}_{4}}\)\(\rm{)}\)\(\rm{{\,\!}_{3}}\)溶液中加入过量\(\rm{NH}\)\(\rm{{\,\!}_{3}}\)\(\rm{·H}\)\(\rm{{\,\!}_{2}}\)\(\rm{O}\):\(\rm{Al}\)\(\rm{{\,\!}^{3+}}\)\(\rm{+4NH}\)\(\rm{{\,\!}_{3}}\)\(\rm{·H}\)\(\rm{{\,\!}_{2}}\)\(\rm{O═}\)\(\rm{AlO}\)\(\rm{\rlap{_{2}}{^{-}}}\)\(\rm{+2H}\)\(\rm{{\,\!}_{2}}\)\(\rm{O+4NH}\)\(\rm{\rlap{_{4}}{^{+}}}\) |