Question

Which of the following on hydrolysis gives sulfuric acid?

• A. sulfur trioxide
• B. sulfur dioxide
• C. sulfur oxide
• D. none of above

Answer 1

The correct option is A sulfur trioxide

$S{O}_3$ is the anhydride of $H_{2}S{O}_4$ Thus, the following reaction occurs:
$S{O}_3+H_{2}O⟶H_{2}S{O}_4$
The reaction occurs both rapidly and exothermically, too violently to be used in large-scale manufacturing. At or above ${340}^{0}C$ sulfuric acid, sulfur trioxide, and water coexist in significant equilibrium concentrations