Factors Affecting Chemical Equilibrium (Le Chatelier's Principle)
Applying Le Chatelier's Principle to predict the effect of changes in concentration, pressure, temperature, and inert gas addition on equilibrium position.
What is Factors Affecting Chemical Equilibrium (Le Chatelier's Principle)?
A state in a reversible reaction where the rate of the forward reaction equals the rate of the reverse reaction, resulting in constant concentrations of reactants and products.
Key points
- Understand the conditions for chemical equilibrium.
- Explain Le Chatelier's Principle.
- Predict the effect of concentration changes on equilibrium.
- Predict the effect of pressure changes on equilibrium.
Common exam trap
Confusing effect of inert gas addition at constant volume vs. constant pressure.
Definitions
- Term
Chemical Equilibrium
- Meaning
A state in a reversible reaction where the rate of the forward reaction equals the rate of the reverse reaction, resulting in constant concentrations of reactants and products.
- Term
Le Chatelier's Principle
- Meaning
A principle stating that if a change of condition (like temperature, pressure, or concentration) is applied to a system in equilibrium, the system will shift in a direction that relieves the stress.
- Term
Endothermic Reaction
- Meaning
A reaction that absorbs heat from its surroundings, indicated by a positive enthalpy change (ΔH > 0).
- Term
Exothermic Reaction
- Meaning
A reaction that releases heat into its surroundings, indicated by a negative enthalpy change (ΔH < 0).
Learning objectives
Understand the conditions for chemical equilibrium.
Explain Le Chatelier's Principle.
Predict the effect of concentration changes on equilibrium.
Predict the effect of pressure changes on equilibrium.
Predict the effect of temperature changes on equilibrium.
Analyze the impact of inert gas addition on equilibrium.
Prerequisites
Concept of chemical equilibrium
Reversible reactions
Endothermic and exothermic reactions
Partial pressures of gases
Common mistakes
Confusing effect of inert gas addition at constant volume vs. constant pressure.
Incorrectly applying pressure changes when the number of moles of gas is the same on both sides.
Forgetting that temperature changes affect the value of K.
Assuming equilibrium shifts only in one direction for all changes.
Keywords
Chemical Equilibrium
Le Chatelier's Principle
Concentration
Pressure
Temperature
Inert Gas
Dynamic Equilibrium
Equilibrium Position
Stress
Counteract
Endothermic
Exothermic
Practice preview
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