\(\begin{array}{l} a)\\ 2{H_2}S + 3{O_2} \xrightarrow{t^0} 2S{O_2} + 2{H_2}O\\ 2S{O_2} + {O_2} \xrightarrow{t^0,V_2O_5} 2S{O_3}\\ S{O_3} + {H_2}O \to {H_2}S{O_4}\\ F{e_2}{O_3} + 3{H_2}S{O_4} \to F{e_2}{(S{O_4})_3} + 3{H_2}O\\ F{e_2}{(S{O_4})_3} + 3BaC{l_2} \to 2FeC{l_3} + 3BaS{O_4}\\ b)\\ 2{H_2}S + S{O_2} \to 3S + 2{H_2}O\\ S + {O_2} \xrightarrow{t^0} S{O_2}\\ S{O_2} + B{r_2} + 2{H_2}O \to {H_2}S{O_4} + 2HBr\\ CuO + {H_2}S{O_4} \to CuS{O_4} + {H_2}O\\ CuS{O_4} + BaC{l_2} \to CuC{l_2} + BaS{O_4}\\ c)\\ Mn{O_2} + 4HCl \to MnC{l_2} + C{l_2} + 2{H_2}O\\ 2Fe + 3C{l_2} \xrightarrow{t^0} 2FeC{l_3}\\ FeC{l_3} + 3AgN{O_3} \to Fe{(N{O_3})_3} + 3AgCl\\ C{l_2} + {H_2} \to 2HCl\\ d)\\ {H_2}S + 4B{r_2} + 4{H_2}O \to 8HBr + {H_2}S{O_4}\\ 2NaCl + {H_2}S{O_4} \to N{a_2}S{O_4} + 2HCl\\ HCl + NaOH \to NaCl + {H_2}O\\ 2NaCl + 2{H_2}O \to 2NaOH + C{l_2} + {H_2}\\ C{l_2} + S{O_2} + 2{H_2}O \to 2HCl + {H_2}S{O_4}\\ e)\\ S{O_2} + 2{H_2}S \to 3S + 2{H_2}O\\ S + {H_2} \xrightarrow{t^0} {H_2}S\\ {H_2}S + Cu{(N{O_3})_2} \to CuS + 2HN{O_3}\\ f)\\ {H_2}S{O_4} + N{a_2}S{O_3} \to N{a_2}S{O_4} + S{O_2} + {H_2}O\\ S{O_2} + NaOH \to NaHS{O_3}\\ S{O_2} + 2NaOH \to N{a_2}S{O_3} + {H_2}O\\ N{a_2}S{O_3} + 2HCl \to 2NaCl + S{O_2} + {H_2}O \end{array}\)
