Question

when you mixed the Hydro Sulfur Oxide and magnesium

Answer 1

If you mean that Hydro Sulfur Oxide (because there is nothing with this name) is the same that sulfuric acid $\mathrm{H}_2\mathrm{SO}_4$ (product of reaction between water (hydro) and sulfur oxide $\mathrm{SO}_3$) the solution is next:

$$\mathrm{Mg} + \mathrm{H}_2\mathrm{SO}_4 \rightarrow \mathrm{MgSO}_4 + \mathrm{H}_2\uparrow$$

When Magnesium reacts with sulfuric acid it gives magnesium sulfate (salt) and hydrogen gas as a products.