Unit 11: Chemical Kinetics: 9.5, 13.1-13.2, 13.5
Energy in Chemical Reactions and Chemical Equilibrium
9.5 Energy in Chemical Reactions
 system & surroundings
 enthalpy
 heat of reaction(Δ enthalpy) & calculations
 endothermic and exothermic processes
13.1 Rates of Reactions
 Collision Theory
 Energy Diagrams
 Activation Energy, Ea
 Factors That Affect Rate
 Temperature
 Concentration
 Catalysts
13.2 Chemical Equilibrium
 Reversible Reactions
13.5 Le Châtelier’s Principle
 Changing Equilibrium Condition
I Can Statements:
(9.5) Energy in Chemical Reactions
1.
2.
3.
4.
Define and distinguish between the System and the Surroundings for a chemical reaction
Define the term enthalpy
Define the term heat (enthalpy) of reaction and relate it to the change in the enthalpy of a system
Define the terms exothermic and endothermic and correctly apply the terms to heats of reaction for
various chemical processes
(13.1) Rates of Reactions
1. Explain the collision theory,and rates of chemical reaction and how they are related to one another
2. Define activation energy, Ea and relate it to rates of chemical reaction
3. State the 3 conditions required for a reaction to occur
 collision of molecules
 proper orientation of colliding molecules
 sufficient energy of colliding molecules
4. List and explain how the following are related to the collision theory and their affect on rates of reaction
 temperature
 concentrations of reactants
 catalysts
5. Identify and interpret each of the following on an energy diagram
 energy of reactants compared to energy of products
 Ea
 ΔHRXN
 exothermic or endothermic reaction
(13.2) Chemical Equilibrium
1. Define and explain the concepts of forward and reverse reactions, and reversible reaction and their
relationship to rate of chemical reaction
2. Define and explain chemical equilibrium in terms of
 reversible reactions
 concentrations of reactants and products
 rates of forward and reverse reaction
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(13.5) Le Châtelier’s Principle
1. State and explain Le Châtelier’s Principle
2. Explain and predict the effect of each of the following on chemical equilibrium
 concentration changes
 volume and pressure changes
 catalysts
 temperature changes
Vocabulary 9.5, 13.1-13.2, 13.5
Activation Energy
Catalyst
Chemical Equilibrium
Collision Theory
Enthalpy
Endothermic
Exothermic
Forward Reaction
Heat (Enthalpy) of Reaction
Le Châtelier’s Principle
Rate of Reaction
Reverse Reaction
Reversible Reaction
System
Surrounding
Achievement Scale 13.1-13.2, 13.5
Goal
B Level
A Level
9.5
Energy in
Chemical
Reactions
 Can define and distinguish between system
and surroundings for a chemical reaction
 Can define and relate the terms enthalpy and
heat of reaction
 Can define and correctly apply the terms
exothermic and endothermic to the heats of
reaction for various chemical processes
C Level
 Can calculate the enthalpy
change for a chemical
reaction and state if that
change for was exothermic
or endothermic based on
the mathematical sign
 Given a chemical
reaction with its
molar enthalpy
value, can use
stoichiometry to
convert between
enthalpy and
amount.
13.1
Rates of
Reaction
 Can define the collision theory of chemical
reactions
 Can define the rate of a chemical reaction
 Can define activation energy
 Can state the 3 requirements for a
reaction to occur
 Can identify and
 Can explain the
interpret the information
effects of
contained in an energy
temperature,
diagram
concentration,
and catalysts on
 Can explain how the
the rate of
collision theory can be
chemical reaction
used to explain rates of
chemical reactions
 Can explain chemical
equilibrium in terms of
reversible reactions,
concentrations of
reactants and products,
and rates of forward and
reverse reaction
 Can predict the effect of  Given a chemical
concentration changes,
equilibrium, can
catalysts, volume and
manipulate the
pressure changes, and
necessary
temperature changes on
variables to
chemical equilibrium
achieve a stated
outcome.
13.2
 Can define and explain the concepts of a
Chemical
forward and reverse reactions and
Equilibrium
reversible reactions and their relationship
to rates of chemical reaction
 Can define chemical equilibrium
13.5
Le
Châtelier’s
Principle
 Can state Le Châteliers Principle
 List what variables will change the
equilibrium of a reaction.
2
Sample Questions 9.5, 13.1-13.2, 13.5
C Level:
1. When the following reaction is performed the temperature increases dramatically - in other words, heat is
actually one of the products of this reaction.
CH4 (g) + 2 O2(g) → CO2 (g) + 2 H2O (l) + heat(energy)
ΔERXN = − 890 kJ/ mol
Explain the meaning ΔERXN = − 890 kJ/ mol in terms of bonding and energy changes for the reaction.
2. What is the name of the theory that states that reactions will only take place when the reacting molecules
collide with the proper energy and orientation?
3. How do catalysts affect the rate of chemical reaction?
4.
(a) Identify what is represented by each of the letters on the following Energy Diagram.
(b) Was this reaction exothermic or endothermic? Justify your answer.
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5. List 3 things that influence the rate of a chemical reaction.
6. State how each of the following would change the rate of the following reaction. Justify your answer in
each case.
2 NO(g) + 2 H2 (g) → N2(g) + 2 H2O(g)
Rate
Justification
(a) Some NO (g) is taken away.
(b) The temperature is decreased.
(c) Some H2(g) is added.
(d) A catalyst is added.
7. What is a reversible reaction?
8.
Write both the forward and reverse reaction for the following reversible reaction.
N2(g) + 3 H2(g)
2 NH3(g)
9. Define chemical equilibrium in terms of:
(a) concentration of reactants and products
(b) rate of reaction
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9. State whether the following statement is TRUE or FALSE. Justify your answer.
At equilibrium the concentrations of reactants and products are equal to each other.
10. State Le Châtelier’s Principle.
11. Ammonia is produced by reacting nitrogen gas and hydrogen gas.
N2(g)
+
3 H2(g)
2 NH3(g) + 92 kJ
For each of the following changes at equilibrium, indicate whether the equilibrium shifts towards product or
reactant or does not shift:
EQULIBRIUM SHIFT
(a) removing N2(g)
(b) adding NH3(g)
(c) lowering the temperature
(d) adding H2(g)
(e) increasing the volume of the container
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