Viết các phương trình hoá học sau :
\(\eqalign{
& Al + HCl \to A + …. \cr
& B \downarrow + {H_2}S{O_4} \to C + … \cr
& B \downarrow \buildrel {{t^o}} \over
\longrightarrow D + … \cr
& A + NaOH \to B \downarrow + … \cr
& C + KOH \to B \downarrow + … \cr
& D\buildrel \text{điện phân nóng chảy} \over
\longrightarrow Al + ….. \cr} \)
\(\eqalign{
& 2Al\,\, + \,\,\,6HCl\,\,\, \to \,\,\,\,2\underbrace {AlC{l_3}}_A\,\, + \,\,\,3{H_2} \uparrow \cr
& 2\underbrace {Al{{(OH)}_3}}_B\,\,\, + \,\,\,3{H_2}S{O_4}\,\,\, \to \,\,\,\underbrace {Al{{(OH)}_3}}_C\,\, + \,\,\,6{H_2}O \cr
& 2\underbrace {Al{{(OH)}_3}}_B\,\,\xrightarrow{{{t^o}}}\,\,\,\underbrace {A{l_2}{O_3}}_D\,\,\, + \,\,\,3{H_2}O \cr
& \underbrace {AlC{l_3}}_A\,\, + \,\,\,\,3NaOH\,\,\, \to \,\,\underbrace {Al{{(OH)}_3}}_B \downarrow \,\, + \,\,3NaCl \cr
& \underbrace {A{l_2}{{(S{O_4})}_3}\,}_C\,\, + \,\,\,6KOH\,\,\, \to \,\,\,\underbrace {Al{{(OH)}_3}}_B\,\,\, + \,\,3{K_2}S{O_4} \cr
& 2A{l_2}{O_3}\,\,\,\xrightarrow{\text{điện phân nóng chảy}}\,\,\,4Al\,\,\, + \,\,3{O_2} \cr} \)