Question #81435
1 Answer
The forward reaction will be favored.
Explanation:
Equilibrium reactions are governed by Le Chatelier's Principle, which states that a system at equilibrium will respond to a stress on the current position of the equilibrium in such a way as to counteract that stress and reestablish the equilibrium.
In your case, you have
2SO2(g)+O2(g)⇌2SO3(g)
Now, when you increase the amount of oxygen, you're placing a stress on the equilibrium.
In order to counteract this stress, the equilibrium will shift in such a way as to decrease the amount of oxygen gas.
This implies that the equilibrium shift to the right. As a result, the forward reaction will be favored, i.e. sulfur dioxide,
2SO2(g)+O2(g)⇌2SO3(g)
aa−−−−−−−−−−−−−−−−−−−→aashift to the rightaaaa
Now, another important thing to notice here is that when the equilibrium shifts to the right, the pressure in the reaction vessel decreases.
This is the case because you have
2 moles SO2+1 mole O2=3 moles gas
on the reactants' side and
2 moles SO3
on the products' side. Since pressure is caused by the collisions that take place between the gas molecules and the walls of the reaction vessel, a decrease in the total number of moles of gas present will cause the pressure to decrease as well.
