Chapter 6

What is dynamic equilibrium?

Both forward and back reactions are happening at equal rates

What is the Haber-Bosch equation?

3 H2 + N2 → NH3

What is the Law of Mass Action?

Given A + B² → C³ + D^4

K = ([C]³ [D]^4)/([A] [B]²)

What is the equilibrium constant?

K

Has no units and is constant at any given temperature

What is included in equilibrium constant calculations?

Gasses and aqueous

NOT solids or pure liquids

What value of K favors products? Reactants?

K < 1 favors reactants

K > 1 favors products

What is Ka?

Acid dissociation constant

What is Kb?

Base association constant

What is Ksp?

Solubility product

What is Kf?

Formation constant

How does K change when an equation runs backwards?

It is inverted

Given A + B² → C³ + D^4

Kinverted = ([A] [B]²)/([C]³ [D]^4)

When you multiply an equation by n, how does K change?

Each term is raised to the power of n

K is raised to the power of n

How does K change when adding equations?

Ks are multiplied

What is LeChatlier’s principle?

If equilibrium is disturbed, the position of the equilibrium will shift to minimize it

How do you change equilibrium (three ways)?

Change the concentration of reactants or products

Change the pressure (volume) in a gas reaction

Change the temperature

How does temperature affect a reaction?

Calculate how it changes using:

G = -RT ln K

R = 8.134

K = equilibrium constant

How does K change when you add heat to an exothermic reaction?

K decreases

How does K change when you add heat to an endothermic reaction?

K increases

What is Q?

Use it in place of K when you do not know if the equation is endothermic or exothermic

How is Q calculated?

Given A + B² → C³ + D^4

Q = ([C]^c [D]^d)/([A]^a [B]^b)

What does it mean when Q = K?

At equilibrium

What does it mean when Q > K?

Reaction will quickly go towards the reactants

What does it mean when Q < K?

Reaction will quickly go towards the products