Question

Al→Al2O3→Al2(SO4)3→Al2(OH)3→Al2O3→K2AlO2

Answer 1

4Al +3 O2 = 2Al2O3

Al2O3 + 3H2SO4 = Al2(SO4)3 +3 H2O

Al2(SO4)3 +6 NaOH = 2Al(OH)3 + 3Na2SO4

2Al(OH)3  = Al2O3 + 3H2O

Al2O3 + 2KOH = 2K2AlO2 + H2O