Chemical Equilibrium and Dynamic Equilibrium

These flashcards cover key concepts related to chemical equilibrium, the equilibrium constant, reaction quotient, and Le Châtelier's Principle, as well as the effect of catalysts and temperature on reactions.

Chemical Equilibrium

The state in a reversible chemical reaction where the rate of the forward reaction equals the rate of the reverse reaction, resulting in constant concentrations of reactants and products.

Dynamic Equilibrium

A state of balance in a chemical reaction where forward and reverse reactions occur at the same rate, leading to no net change in concentrations.

Equilibrium Constant (K)

The ratio of product concentrations to reactant concentrations each raised to the power of their stoichiometric coefficients, excluding pure solids and liquids.

K≫1

Indicates that the equilibrium lies to the right, favoring product formation.

K≪1

Indicates that the equilibrium lies to the left, favoring reactant formation.

K≈1

Indicates that there are appreciable amounts of both reactants and products at equilibrium.

Reaction Quotient (Q)

Calculated in a similar way to K but with concentrations at any moment, helping to predict the direction of the reaction.

Q<K

Indicates that the reaction proceeds to the right (forward) to produce more products.

Q>K

Indicates that the reaction proceeds to the left (reverse) to produce more reactants.

I.C.E. Table

A table used to keep track of Initial concentrations, Change in concentrations, and Equilibrium concentrations.

The 5% Rule

Allows the assumption that 'x' is negligible if the initial concentration is at least 100 times greater than the value of K.

Le Châtelier's Principle

States that if a stress is applied to a system in equilibrium, the system will shift in a direction that relieves the stress.

Effect of Adding Substances (Le Châtelier's Principle)

The equilibrium shifts to consume the added substance.

Effect of Removing Substances (Le Châtelier's Principle)

The equilibrium shifts to produce more of the removed substance.

Effect of Changing Volume on Gaseous Equilibrium

Decreasing volume shifts the equilibrium toward the side with fewer moles of gas; increasing volume shifts it toward more moles of gas.

Effect of Temperature Change (Endothermic Reaction)

Increasing temperature shifts the equilibrium to the right (product side).

Effect of Temperature Change (Exothermic Reaction)

Increasing temperature shifts the equilibrium to the left (reactant side).

Effect of Catalyst on Equilibrium

A catalyst increases the rate of both reactions but does not affect the position of equilibrium or the value of K.