Equilibrium Flashcards
Reactions that proceed in one direction only are termed ______.
Irreversible
Reactions that can proceed in the forward and reverse direction are known as ______.
Reversible
When a reaction system is closed and no reactants or products are added or removed, the system will eventually settle into a state in which the rate of the forward reaction equals the rate of the reverse reaction. This state is known as _____ _____.
Dynamic equilibrium. The concentrations of the reactants and products will remain the same once dynamic equilibrium has been reached.
For a generic reversible reaction aA + bB –> cC + dD, the law of ____ ____ states that, if the system is at equilibrium at a constant temperature, then the following ratio is constant: k sub eq equals ?
Mass action; k sub eq = ([C]^c[D]^d)/([A]^a[B]^b)
When dealing with gases, the equilibrium constant is referred to as _____.
k sub p; the subscript p indicates that it is in terms of pressure
True or false: When a reaction has reached dynamic equilibrium, the concentrations of the reactants and products are equal.
False. The RATES of the forward and reverse are equal, but not necessarily the concentrations of reactants and products.
True or false: In equilibrium expressions, the exponents are related to the coefficients of the balanced chemical equation.
True. Remember that in RATE LAWS, the exponents must be determined experimentally.
Equilibrium takes time to achieve. What measurement can we use to assess how far a reaction has gone toward equilibrium?
The reaction quotient, Q. It takes the same form as k sub eq (or k sub c) and simply uses the current concentrations of reactants and products.
If Q is LESS THAN k sub eq, what does this imply?
The forward reaction has not yet reached equilibrium. Its delta G is less than 0 and the reaction will continue spontaneously in the forward direction.
If Q equals k sub eq, then the reaction has reached _____ _____.
Dynamic equilibrium. Delta G is equal to 0 in this scenario.
If Q is GREATER THAN k sub eq, what does this imply?
The forward reaction has exceeded equilibrium. The reverse rate of reaction is increased to restore equilibrium. The delta G of the reverse reaction is less than 0 in this case.
The concentrations of pure ____ and pure ____ are not included in the equilibrium expression.
Solids; liquids
If the equilibrium constant for a reaction is written in one direction as k sub eq, the equilibrium constant for the reverse reaction is ____.
(1/k sub eq)
What principle states that if a stress is applied to a system, the system shifts to relieve that applied stress?
Le Chatlier’s principle
