# Question #f3551

Aug 16, 2017

$2 S {O}_{2} + {O}_{2} \to 2 S {O}_{3}$
Synthesis

#### Explanation:

Write the unbalanced equation:

$S {O}_{2} + {O}_{2} \to S {O}_{3}$

The left side of the equation has one more oxygen atom than the right side, so half the coefficient of ${O}_{2}$

$S {O}_{2} + \frac{1}{2} {O}_{2} \to S {O}_{3}$

Double all coefficients:

$2 S {O}_{2} + {O}_{2} \to 2 S {O}_{3}$

This equation is now balanced because there are two S atoms and six O atoms on each side.

Because the reaction has the form of $A + B \to A B$, this is a synthesis reaction.