\(1,6HCl+2Fe\left(OH\right)_3\rightarrow2FeCl_3+6HCl\\ 2,Ba\left(OH\right)_2+H_2SO_4\rightarrow BaSO_4+2HCl\\ 3,Fe+S\xrightarrow[]{t^0}FeS\\ 4,Ba\left(OH\right)_2+CO_2\rightarrow BaCO_3+H_2O\\ 5,O_2+2Mg\xrightarrow[]{t^0}2MgO\\ 6,2H_2O+2Al+2NaOH\rightarrow2NaAlO_2+3H_2\)