$\text{Ba}{{\left( \text{Cl}{{\text{O}}_{3}} \right)}_{2}}+{{\text{H}}_{2}}\text{S}{{\text{O}}_{4}}\to \underset{(Y)}{\mathop{2\text{HCl}{{\text{O}}_{3}}}}\,+\text{BaS}{{\text{O}}_{4}}\downarrow $

$2\text{HCl}{{\text{O}}_{3}}\overset{{}}{\mathop{\frac{\Delta }{\Delta >365\,\text{K}}}}\,2\text{Cl}{{\text{O}}_{2}}+{{\text{H}}_{2}}\text{O}+\frac{1}{2}{{\text{O}}_{2}}$