Equilibrium Constant
What phases are included in an equilibrium constant?
Gaseous and aqueous
What does Le Chatelier's Principle determine?
If you disturb a system at equilibrium, it will shift so as to minimize the disturbance.
4A (g) + 3B (g) <---> 5C (g) Initially, 10 mol A and 15 mol B are put in a 5L flask. What are the initial concentrations of A, B, and C?
2 M, 3 M, 0 M.
What does the reaction quotient determine?
Which way the equilibrium runs
If a reaction is spontaneous in the forward direction, it is ______ favored.
Products favored
When is Keq reactant favored?
When it less than 1/1000
Name 4 factors that will shift a system at equilibrium!
Concentration, temperature, volume, pressure!
What does the change from initial to final concentration represent
The amount of reactant that reacts
If Q=Keq which way does the system run?
The system is at equilibrium
Entropy is…
A measure of disorder in a system
What is the equilibrium constant for this reaction? 4A(g) + 2B(g) <—> 3C (g)
[C]^3 / [A]^4 [B]^2
if you decrease volume…
System shifts to side with less molecules!
P2 + 3H2 <---> 2PH3 Initially, 4 mol P2 and 8 mol H2 are put in a 2L flask. Which way will the reaction run?
To the right
If Q>K which way does the system run?
To the left
Dynamic equilibrium means…
When the rate of the forward reaction is equal to that of the reverse reaction.
What is the difference between Kp and Kc?
They’re both equilibrium constants but Kp s based on the partial pressure of the gases whereas Kc is the concentration
If the reaction is exothermic and you add energy…
The reaction shifts left (to the reactants)!
H2 + F2 <---> 2HF Initially, 10 mol H2 and 6 mol F2 are in a 2L flask. At eqm, 5 mol HF are present. Draw and fill in the ICE diagram on the board
Initial, Change, Equilibrium!
If Q<K which way does the system run?
To the right
Equilibrium occurs when…
The rate of the former reaction is equal to the rate of the reverse reaction
What happens when we multiply a reaction by a factor of n?
K(new)=K(old)^n
If the reaction is exothermic and you add energy…
The reaction shifts right to the products!
N2 + 3H2 <---> 2NH3 Initially, 12 mol NH3 are put in a 2L flask. At equilibrium, the concentration of N2 is 1 M. What is the Keq?
Keq=5.93x10^1
How is the Q calculated?
Same as Keq but with initial concentrations
Equilibrium is _______ dependent
A. Volume
B. Temperature
C. Concentration
D. Rate
B. Temperature!