Change in equilibrium
Answer:
A. The equilibrium shifts right to produce more SO₃ molecules.
Explanation:
Le Châtelier’s Principle states that if you apply a stress to a system at equilibrium the system will respond in a way that will reduce the stress.
Here, the stress is the addition of oxygen. The system will respond by trying to remove the added oxygen.
Thus, the position of equilibrium will move to the right.
Adding O₂ increases the number of collisions between SO₂ and O₂ molecules. More collisions means more successful collisions, so more SO₃ is formed.
Change in concentration
Answer:
B. The rate of the reverse reaction increases with an increase in the concentration of CaO(s) and CO₂(g).
Explanation:
You can’t change the concentration of a solid.
Concentration = mass/volume (= density), and the density of a solid is constant.
Changing the amount of a solid has no effect on the rate of a reaction.
Thus, we need consider only the effect of adding or removing a gas.
If we want to increase the rate of the reverse reaction, we must increase the concentration of the CO₂.
Then, more CO₂ molecules will come into contact with the solid and be captured as solid CaCO₃.
