Write the reaction equation: S → SO2 → H2SO4 → Na2SO4 → PbSO4

In solving a chain of transformations, it is required to compose four reaction equations.
1. Oxidation of sulfur with oxygen:
2S + 3O2 = 2SO3 oxidation reaction;
2. The interaction of acidic oxide SO2 leads to the formation of acid:
SO3 + H2O = H2SO4
3. Sulfuric acid actively interacts with the basic oxide:
Exchange reaction H2SO4 + Na2O = Na2SO4 + H2O
4. Sodium sulfide reacts with barium chloride salt:
Na2SO4 + PbCl2 = 2NaCL + PBSO4
The ion exchange reaction goes to the end, and lead sulfate is formed in the precipitate.