Al-Al2O3-AlCl3-Al(OH)3-Al2O3-Al2(SO4)3-Al(NO3)3

`4Al+3O_2`  $\xrightarrow{t^o}$  `2Al_2O_3`

`Al_2O_3+6HCl->2AlCl_3+3H_2O`

`AlCl_3+3KOH->Al(OH)_3+3KCl`

`2Al(OH)_3`  $\xrightarrow{t^o}$  `Al_2O_3+3H_2O`

`Al_2O_3+3H_2SO_4->Al_2(SO_4)_3+3H_2O`

`AL_2(SO_4)_3+3Ba(NO_3)_2->3BaSO_4+2Al(NO_3)_3`