Giải thích các bước giải:
\[\left\{ \begin{array}{l} Mg\\ Al\\ Ag\\ Na \end{array} \right.\xrightarrow{+HCl\ \rm{du}}\left\langle \begin{array}{l} Ag\\ \left\{ \begin{array}{l} MgC{l_2}\\ AlC{l_3}\\ NaCl\\ HCl \end{array} \right. \end{array} \right.\xrightarrow{\rm{co \ can}}\begin{cases}MgCl_2\\ AlCl_3\\ NaCl\end{cases}\xrightarrow{+KOH \ \rm{du}} \left\langle \begin{array}{l} \downarrow :Mg{(OH)_2}\xrightarrow{+HCl \ \rm{du}, \rm{co \ can}} MgCl_2\xrightarrow{\rm{dpdd}} Mg\\ {\rm{dd}}:\;\left\{ \begin{array}{l} KCl\\ KAl{O_2}\\ NaCl\\ KOH \end{array} \right.\xrightarrow{+CO_2\ \rm{du}} \end{array} \right.\left\langle \begin{array}{l} \downarrow :Al{(OH)_3}\xrightarrow{+HCl\ \rm{du,co\ can}}AlCl_3\xrightarrow{\rm{dpcnc}}Al\\ {\rm{dd}}:\left\{ \begin{array}{l} KCl\\ NaCl\\ KHC{O_3} \end{array} \right.\xrightarrow{t^\circ} \begin{cases}KCl\\ NaCl\end{cases}\xrightarrow{\text{ket tinh dd bao hoa}}\left\langle \begin{array}{l} KCl\\ NaCl\xrightarrow{\rm{dpnc}} Na \end{array} \right. \end{array} \right.\]