Final answer:
Sulfur dioxide reacts with oxygen to form 1. sulfur trioxide (SO₃), as part of the industrial production process for sulfuric acid.
Step-by-step explanation:
Sulfur dioxide reacts with oxygen to form sulfur trioxide, which is represented by the chemical formula 1. SO₃. This reaction is part of the process used in the industrial production of sulfuric acid.
The balanced chemical equation for the reaction is:
2SO₂(g) + O₂(g) → 2SO₃(g).