Kinetics
Collision Theory
Particles must collide in the right orientation with the right energy
If a reactant is added to the system, the reaction will shift in this direction.
Towards the right (product) side
rate of forward reaction = rate of reverse reaction
equilibrium
Na+OH <---> NaOH Na is 0.500M, OH is 0.600M, and NaOH is 0.800M. What is the Keq of the equation?
What is 0.800/(0.500)(0.600) = 2.67
A step by step description of the series of events, usually collisions, that lead to a reaction.
reaction mechanism
Overall reaction order? Rate=k [Br-] [BrO3-] [H+]2
4th order
If a reactant is taken away from the system, the reaction will shift in this direction.
shift towards the reactant side
When reaction is at equilibrium, the forward and reverse reactions cease to occur.
True or False?
False
Two physical states that are not included in Keq calculations
solids and liquids
This step is always the rate-determining step in a reaction.
slowest step
The minimum energy that colliding particles must have in order to react.
What is activation energy?
2SO2(g) + O2(g) <--> 2SO3(g) endothermic
What happens to equilibrium is temperature is increased?
Shift towards the right (product) side
4A (g) + 2B (g) <---> 3C (g) What is the equilibrium expression?
K = [C]^3 / [A]^4 [B]^2
Given the following equilibrium:
A(g) + B(g) <-- --> C(g) Keq = 10
What is the Keq for:
C(g) <-- --> A(g) + B(g) Keq = ?
1/10 or 0.10
What is a substance that is made in one step and then used up in the step?
an intermediate
The graph of ln A vs time shows the most linear trend. What is the reaction order of A?
1st order
If you have the following equation:
3 A (s) + B (g) <-- --> 2 C (g) + 3 D (g),
and the pressure is decreased, the reaction will shift in which direction?
shift towards the product (right) side.
Given the following equilibrium:
2 A (g) + 4B (aq) + C(l) <---> 8D (s) + 2 E (s)
What is the Keq set up?
Keq = 1 / [A]^2 [B]^4
Given the following equilibrium:
A(g) + B(g) <-- --> C(g) Keq = 10
What is the Keq for:
2 C(g) <-- --> 2 A(g) + 2 B(g) Keq = ?
(1/10)^2 = 0.010
2NO(g)⇌N2O2(g)(Step 1 fast) N2O2(g)+O2(g)⟶2NO2(g)(Step 2 slow)
For the following reaction, this step is the rate-determining step.
Step 2
The graph of 1/[A] vs time produces the best linear fit. The linear equation is y = 1.56 x + 12.1
What is the value of the rate constant k and its unit?
1.56 1/Ms
Given the following equilibrium reaction:
2SO2(g) + O2(g) <--> 2SO3(g)
What happens to equilibrium if neon gas is added?
no change
What direction is the reaction shifting towards to if Q>K?
shift towards the reactant side
Given the following equilibrium reactions
(1) A(g) <-- --> B(g) Keq = 10
(2) B(g) <-- --> C(g) Keq = ?
--------------------------------------
A(g) <-- --> C(g) Keq = 25
10 x (Keq 2) = 25
Keq 2 = 2.5
2NO(g) ⇌ N2O2(g)(Step 1 fast)
N2O2(g) + O2(g) ⟶ 2NO2(g)(Step 2 slow)
In this reaction, this substance is considered the intermediate.
N2O2