Consider the equilibrium reaction
CO(g)+H2O(g)⇋CO2(g)+H2(g)
Determine how each change in the left-hand column will stress the system and in which direction the equilibrium reaction will shift in response.
if you increase either of the reactants concentration, shift to the right. Change in temp? no shifting. Adding CO? shifts to right.
Don't for get about Pressure-Volume effects. Changes in Pressure-Volume will not affect this reaction b/c molar volumes of gas are equal on both sides of equation. However, Vm(Reactants)>Vm(Products), increasing pressure (decreasing volume) shifts reaction to lower molar volume side; or if pressure is decreased, reaction will shift to the higher molar volume side. If Vm(Reactants)<Vm(Products), shifts will be opposite of Vm(R)>Vm(P).
To determine how each change in the left-hand column will stress the system and in which direction the equilibrium reaction will shift, we need to consider Le Chatelier's principle. According to this principle, when a system at equilibrium is subjected to a change, it will shift in a way that opposes the change and restores equilibrium.
1. Change: Adding more CO(g)
Stress on the system: Increase in CO concentration
Equilibrium shift: The equilibrium will shift towards the right to consume the additional CO. This means more CO2 and H2 will be formed.
2. Change: Removing H2O(g)
Stress on the system: Decrease in H2O concentration
Equilibrium shift: The equilibrium will shift towards the left to replace the lost H2O. This means more CO(g) and H2(g) will be formed and less CO2(g) and H2(g) will be consumed.
3. Change: Increasing the pressure
Stress on the system: Increased pressure
Equilibrium shift: The equilibrium will shift towards the side with fewer moles of gas to reduce the pressure. In this case, the left side has only 1 mole of gas (CO), while the right side has 2 moles of gas (CO2 and H2). Therefore, the equilibrium will shift towards the right to reduce the pressure by producing more CO2 and H2.
4. Change: Decreasing the temperature
Stress on the system: Decrease in temperature
Equilibrium shift: The reaction is exothermic (releases heat). According to Le Chatelier's principle, the equilibrium will shift in the direction that produces more heat. Therefore, the equilibrium will shift towards the left, favoring the reverse reaction, to produce more CO and H2, which are the reactants and release heat.
It is important to note that these predictions are based on the assumption that the forward reaction is exothermic (releases heat) and the coefficients in the balanced equation represent the stoichiometry of the reaction.
To determine how each change in the left-hand column will stress the system and in which direction the equilibrium reaction will shift, we need to understand Le Chatelier's principle. Le Chatelier's principle states that if a system at equilibrium is subjected to a change, the system will shift in a way that minimizes the effect of the change.
Now let's analyze the different changes one by one and see how they will affect the system:
1. Increasing the concentration of CO:
- This change increases the concentration of reactant CO.
- According to Le Chatelier's principle, the system will shift in the direction that consumes the added CO to relieve the stress.
- Therefore, the equilibrium will shift to the right, favoring the formation of products CO2 and H2.
2. Decreasing the concentration of H2O:
- This change decreases the concentration of reactant H2O.
- According to Le Chatelier's principle, the system will shift in the direction that replaces the lost H2O to relieve the stress.
- Therefore, the equilibrium will shift to the left, favoring the formation of reactants CO and H2O.
3. Increasing the concentration of CO2:
- This change increases the concentration of product CO2.
- According to Le Chatelier's principle, the system will shift in the direction that consumes the added CO2 to relieve the stress.
- Therefore, the equilibrium will shift to the left, favoring the formation of reactants CO and H2O.
4. Increasing the concentration of H2:
- This change increases the concentration of product H2.
- According to Le Chatelier's principle, the system will shift in the direction that consumes the added H2 to relieve the stress.
- Therefore, the equilibrium will shift to the left, favoring the formation of reactants CO and H2O.
In summary:
- Increasing the concentration of a reactant will shift the equilibrium towards the products.
- Decreasing the concentration of a reactant will shift the equilibrium towards the reactants.
- Increasing the concentration of a product will shift the equilibrium towards the reactants.
- Decreasing the concentration of a product will shift the equilibrium towards the products.