2 moles of [tex]SO_2[/tex] and 1 mole of [tex]O_2[/tex] make oxygen gas the limiting reagent.
A limiting reagent can be defined as the chemical element (reactant) that is completely consumed or used up in a chemical reaction.
This ultimately implies that, the amount of chemical element (product) that is formed is limited by this reagent because the chemical reaction can't proceed or continue without it.
The production of sulfur trioxide is given by this properly balanced chemical reaction:
[tex]2SO_2 + O_2 \rightarrow 2SO_3[/tex]
For the above chemical reaction, 2 moles of [tex]SO_2[/tex] and 1 mole of [tex]O_2[/tex] make oxygen gas the limiting reagent.
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