Collision Theory
Energy Diagrams
Miscellaneous
Le Chatelier
Equilibrium Constant Expression
100
_____________ (increasing / decreasing) will increase the number of collisions between molecules and ____________ (increase / decrease) the rate of reaction.
increasing, increase
100
Identify the activated complex.
C
100
_____________ are catalysts found in living organisms that increase the rate of reactions in cells.
enzymes
100
What is true of a system at equilibrium?
A. the concentrations of products and reactants are equal
B. the system is open so that products can escape
C. the reaction has gone to completion
D. the rate of the forward and reverse reactions are equal
D
100
What two phases are included in the equilibrium constant expression?
A. solids
B. liquids
C. gases
D. solutions
C and D
200
Reaction rate is defined by the change in _________ divided by the change in ________.
concentration, time
200
Is the reaction shown exothermic or endothermic?
endothermic
200
The forward reaction moves to the ___________ (left / right), while the reverse reaction moves to the (left / right).
right, left
200
How would decreasing the pressure affect the following reaction at equilibrium?
N2O4 (g) ⇌ 2 NO2 (g)
equilibrium shifts to the right
200
The equilibrium constant expression for K examines the ratio of concentrations of __________ (reactants / products) over the concentrations of _____________ (reactants / products).
products, reactants
300
Chemical ___________ involves the study of reaction rates and pathways.
A. kinetics
B. equilibrium
C. collision theory
D. mechanisms
A. kinetics
300
What is B in the diagram below?
activation energy
300
A ________ _________ occurs when a reaction mechanism creates highly reactive elements that propagate the reaction, like knocking down a series of dominos.
chain reaction
300
How would decreasing [NO2] affect [N2O4] in the following reaction?
N2O4 (g) ⇌ 2 NO2 (g)
[N2O4] increases
300
Write the equilibrium constant expression for the following reaction:
H2 (g) + I2 (g) ⇌ 2 HI (g)
K= [HI]2/([H2][I2])
400
Name four ways to increase the rate of a reaction.
increase temperature, increase concentration, increase surface area, add a catalyst
400
Which shows the net change in energy for the reaction, Δ H or enthalpy?
D
400
Which of the following reactions would be more likely to occur in a single step?
A. H2 (g) + I2 (g) ⇌ 2 HI (g)
B. 2 C2H11 (l) + 15O2 (g) → 12 CO2 (g) + 6 H2O
A
400
How would increasing temperature affect the equilibrium of the following reaction?
H2 (g) + I2 (g) ⇌ 2 HI (g) + heat
equilibrium would shift to the left (reverse reaction)
400
A value of K (less than / greater than) 1 favors the reverse reaction.
less than
500
How does decreasing the volume of a gaseous system affect the rate of reaction?
increases rate of reaction
500
What effect is demonstrated in the diagram below?
catalyst lowers activation energy
500
Give one example of a homogenous catalyst.
gastric juice in the stomach
500
How would temperature change if the pressure was increased in the following reaction?
N2 + 2 O2 + heat ⇌ 2 NO2
temperature would decrease
500
For the reaction 2 H2 (g) + S2 (g) ⇌ 2 H2S (g)
the equilibrium concentrations at 700°C were:
[H2] = 0.208 M
[S2] = 1.13x10-6 M
[H2S] = 0.725 M
Calculate the value of K at 700°C
1.075 x 107