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Volume and Limiting Reactants

APCHEM-T85LWY

Consider the following reaction taking place in a container fitted with a movable piston.

$${ 2SO }_{ 2 }(g)+{ O }_{ 2 }(g)\rightarrow 2{ SO }_{ 3 }(g)$$

Suppose we place two moles each of ${ SO }_{ 2 }$ and ${ O }_{ 2 }$ in the reaction vessel at 25$^{ \circ }$C and adjust the volume to give a total pressure of 1.0 atm. The reaction is ignited by a spark and goes to completion. The temperature is returned to 25$^{ \circ }$C.

Which of the following BEST describes this system after the reaction is complete?

A

${ SO }_{ 2 }$ is limiting. The volume of the system remains the same.

B

Neither reactant is limiting. The volume of the system decreases.

C

${ SO }_{ 2 }$ is limiting. The volume of the system decreases.

D

${ O }_{ 2 }$ is limiting. The volume of the system remains the same.