Consider the following reaction taking place in a container fitted with a movable piston.
2 SO2(g) + O2(g) → 2 SO3(g)
Suppose we place two moles each of SO2 and O2 in the reaction vessel at 25oC 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 25oC. Which of the following BEST describes this system after the reaction is complete?
a O2 is limiting. The volume of the system remains the same.
b SO2 is limiting. The volume of the system remains the same.
c SO2 is limitnig. The volume of the system decreases.
d Neither reactant is limiting. The volume of the system decreases.