Answer:
The stress that will shift the equilibrium system to the right is decreasing the temperature
Explanation:
Chemical equilibrium
This is a state where there is no observable changes in the properties of the system with time.
From the above, a French scientist establishes a principle which states that when an external constraints such as change in temperature, pressure and concentration is imposed on a system in equilibrium, the equilibrium will shift to neutralise the effect.
Furthermore, the principle explained that:
An increase in temperature of an exothermic reaction (i.e ΔH= –ve) will shift the equilibrium backward.
A decrease in temperature of an exothermic reaction (i.e ΔH= –ve) will shift the equilibrium forward.
An increase in temperature of an endothermic reaction (i.e ΔH= +ve) will shift the equilibrium forward.
A decrease in temperature of an exothermic reaction (i.e ΔH= +ve) will shift the equilibrium back.
How to determine which stress that will shift the equilibrium forward (right)
2SO₂(g) + O₂(g) ⇌ 2SO₃(g); ΔH= –98.8 KJ/mol
From the equation above, we can see that the reaction is exothermic reaction (i.e ΔH= –ve).
Therefore, decreasing the temperature will shift the equilibrium to the right.