Answer:
Sulfur dioxide + 2 ( water ) -----> sulfurous acid + water /
SO2 + 2 ( H2O ) -----> H2SO3 + H2O
Explanation:
This formula may not be right. Sulfur dioxide tends to react with water to produce sulfurous acid as per it's formula, but then again that chemical reaction need not be balanced. However, I will solve for either case here -
Sulfur dioxide + water -----> sulfurous acid,
Sulfur dioxide + water -----> sulfurous acid + water
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As I mentioned before, Sulfur dioxide + water -----> sulfurous acid is a chemical reaction that need not balancing as the number of each element present on the reactant and product side are the same. To help, let me rewrite this reaction -
SO2 + H2O -----> H2SO3,
Reactant | Product
Sulfur = 1, Sulfur = 1,
Oxygen = 3, Oxygen = 3,
Hydrogen = 2 Hydrogen = 2
And hence the equation is already balanced. Now let us consider the case we supposedly have at hand - Sulfur dioxide + water -----> sulfurous acid + water. Take a look at the attachment below;