Sulfur dioxide (SO2) can react with water to form sulfurous acid (H2SO3). Sulfurous acid can further react with calcium ions to form calcium sulfite (CaSO3). Finally, calcium sulfite can oxidize to form calcium sulfate (CaSO4).
Sulfur dioxide (SO2) can react with water to form sulfurous acid (H2SO3). Sulfurous acid can further react with calcium ions to form calcium sulfite (CaSO3). Finally, calcium sulfite can oxidize to form calcium sulfate (CaSO4).