Chapter 6 Chemical Equilibrium
Material Equilibrium (a) Chemical equilibrium, which is equilibrium with respect to conversion of one set of chemical species to another set. (b) Phase equilibrium, which is equilibrium with respect to transport of matter between phases of system.
2NO 2 (g) →N 2 O 4 (g)
H 2 O+CO → H 2 +CO 2
Equilibrium Constant K a : acid dissociation constant (HA H + +A - ) K b =K w /K a (A - +H 2 O HA+OH - ) K w =1× (H 2 O H + +OH - ) K sp : solubility product constant
The Standard Concentration Equilibrium Constant K c : equilibrium constant expressed by concentration K p : equilibrium constant expressed by pressure aA+bB→cC+dD △ =(c+d)-(a+b)
Nonideal Mixture Activity and Activity Coefficients
Heterogeneous Equilibra
Application of the Equilibrium Constant - Reaction Quotient 1. Q=K, equilibrium 2. Q>K, the system shifts to the left 3. Q<K, the system shifts to the right
Le Châtelier’s Principle If a change in conditions is imposed on a system at equilibrium, the equilibrium position will shift in a direction that tends to reduce that change in conditions. If a reactant or product is added to a system at equilibrium, the system will shift away from the added component. If a reactant or product is removed, the system will shift toward the removed component
The Effect of a Change in Concentration If a reactant or product is added to a system at equilibrium, the system will shift away from the added component. If a reactant or product is removed, the system will shift toward the removed component.