Question

K2S→H2S→SO2→SO3→AL2(SO4)3→Al(OH)3→Al2O3

Answer 1

K2S + 2HCl->2KCl + H2S
 2H2S + 3O2 -> 2SO2 + 2H2O
 2SO2 + O2 -> 2SO3
 3SO3 + Al2O3 -> Al2(SO4)3
 Al2(SO4)3 + 6NaOH -> 2Al(OH)3 +3 Na2SO4
 2Al(OH)3 -> Al2O3 + 3H2O

Answer 2

K2S+2HCl-->2KCl+H2S↑
2H2S+3O2-->2SO2+2H2O (t)
2SO2+O2-->2SO3 (t, кат. V2O5)
3SO3+Al2O3-->Al2(SO4)3
Al2(SO4)3+6NaOH(разб.)-->2Al(OH)3↓+3Na2SO4
2Al(OH)3-->Al2O3+3H2O (t)