Đáp án đúng: D NH3. $\begin{array}{l}{2Al(OH}{{{)}}_{{3}}}\,{+}\,{6KHS}{{{O}}_{{4}}}\,\xrightarrow{{}}\,{A}{{{l}}_{{2}}}{{{(S}{{{O}}_{{4}}}{)}}_{{3}}}\,{+}\,{3}{{{K}}_{{2}}}{S}{{{O}}_{{4}}}\,{+}\,{3}{{{H}}_{{2}}}{O}\\{2Al(OH}{{{)}}_{{3}}}\,{+}\,{3}{{{H}}_{{2}}}{S}{{{O}}_{{4}}}\,\xrightarrow{{}}\,{A}{{{l}}_{{2}}}{{{(S}{{{O}}_{{4}}}{)}}_{{3}}}\,{+}\,{3}{{{H}}_{{2}}}{O}\\{Al(OH}{{{)}}_{{3}}}\,{+}\,{NaOH}\,\xrightarrow{{}}\,{NaAl(OH}{{{)}}_{{4}}}\end{array}$
