1/ 4Al+3O2->2Al2O3

2/ 4K+O2->2K2O

3/ 2Al(OH)3-->Al2O3+3H2O

4/ Al2O3+6HCl->2AlCl3+3H2O

5/ 2Al+6HCl->2AlCl3+3H2

6/ FeO+2HCl->FeCl2+H2O

7/ Fe2O3+3H2SO4->Fe2(SO4)3+3H2O

8/ 2NaOH+H2SO4->Na2SO+2H2O

9/ 3Ca(OH)2+2FeCl3->3CaCl2+2Fe(OH)3

10/ BaCl2+H2SO4->BaSO4+2HCl

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