Chapter 15 Vocabulary Flashcards
Chemical Equilibrium
A state of dynamic balance in which the rate of formation of the products of a reaction from the reactants equals the rate of formation of the reactants from the products; at equilibrium the concentrations of the reactants and products remain constant.
Haber Process
The catalyst system and conditions of temperature and pressure developed by Fritz Haber and coworkers for the formation of NH3 from H2 and N2.
Law of Mass Action
The rules by which the equilibrium constant is expressed in terms of the concentrations of reactants and products, in accordance with the balanced chemical equation for the reaction.
Equilibrium Constant Expression
The expression that describes the relationship among the concentrations (or partial pressures) of the substances present in a system at equilibrium. The numerator is obtained by multiplying the concentrations of the substances on the product side of the equation, each raised to a power equal to its coefficient in the chemical equation. The denominator similarly contains the concentrations of the substances on the reactant side of the equation
Equilibrium Constant Kc- Kp
The numerical value of the equilibrium-constant expression for a system at equilibrium. The equilibrium constant is most usually denoted by Kp for gas-phase systems or Kc for solution-phase systems
Homogeneous Equilibrium
The equilibrium established between reactant and product substances that are all in the same phase.
Heterogeneous Equilibrium
The equilibrium established between substances in two or more different phases, for example, between a gas and a solid or between a solid and a liquid. (Section 15.4)
Reaction quotient (Q)
The value that is obtained when concentrations of reactants and products are inserted into the equilibrium expression. If the concentrations are equilibrium concentrations, Q = K; otherwise, Q ≠ K. (Section 15.6)
Le Chatelier’s Principle
A principle stating that when we disturb a system at chemical equilibrium, the relative concentrations of reactants and products shift so as to partially undo the effects of the disturbance.
