1. Assign. #13. 1 Dynamic Equilibrium and Equilibrium Constants

2. Equilibrium and Rates ⇌ The equilibrium below is two reactions:
N2O 2NO2
There is the forward reaction:
The reverse reaction is:
At equilibrium the rate of the forward reaction is equal to the reverse reaction: ⇌
Write the rate laws for both the forward and reverse reactions

3. Dynamic Equilibrium
At equilibrium, the rate of the forward and reverse reaction are equal, but continue to occur.
We are at dynamic equilibrium because the reaction is occurring, but rates are equal.

5. Equilibrium Constants (K)
The ratio of products to reactants in equilibrium is known as the equilibrium constant (K)
Only written for aqueous and gaseous substances. Liquids and gases do not participate in equilibrium.
For the general reaction:
aA (aq) + bB (aq) cC (aq) + dD (aq)
The equilibrium constant (Kc) for all aqueous substances is: ⇌

6. Gaseous Equilibrium Constants (Kp)
When the substances in an equilibrium, we can calculate the equilibrium constant using partial pressures.
This is represented as Kp
Kp≠Kc
For the equilibrium:
aA (g) + bB (g) cC (g) + dD (g) ⇌

7. Class Example
Write the equilibrium constant for the following equilibrium:
2 NO (g) + Cl2 (g) 2NOCl (g) ⇌

8. Ag+ (aq) + 2 NH3 (aq) Ag(NH3)2+ (aq)
Table Talk
Write the equilibrium constant for the following equilibrium:
Ag+ (aq) + 2 NH3 (aq) Ag(NH3)2+ (aq) ⇌

9. Quick Write
Which side of the equilibrium do you think is favored in the reaction below based on the value of Kp. Justify your response.
CO (g) + Cl2 (g) COCl2 (g)
Kp = 4.56 x 109 ⇌

10. What K Tells Us
A large K indicates that there are more products than reactants at equilibrium
A small K indicates that there are more reactants than products at equilibrium
If K >> 1, then it is products favored
If K << 1, then it is reactants favored

11. Class Example
After mixture of hydrogen and nitrogen gases in a reaction vessel are allowed to attain equilibrium at 472 oC, it is found to contain 7.38 atm H2, 2.46 atm N2, and atm NH3. From these data calculate the equilibrium constant, Kp, and state whether it is product or reactants favored:
N2 (g) + 3 H2 (g) NH3 (g) ⇌