What is the oxidation state of sulfur in sulfurous acid?
The oxidation state of sulfur in sulfurous acid (H2SO3) is +4.
Complete the following task based on the instruction and optional input provided.### Instruction:
What is the oxidation state of sulfur in sulfurous acid?

### Output:
The oxidation state of sulfur in sulfurous acid (H2SO3) is +4.