
Spring 2009 

Exercise: Reaction Diagrams & Chemical Equilibrium 


Discussion Modules 


Reactants Products + Energy
Draw a reaction coordinate diagram for this reaction and label it completely.
Reactants + Energy Products
Draw a reaction coordinate diagram for this reaction and label it completely.
Reactants Products + Energy
Draw a reaction coordinate diagram for this reaction showing the uncatalyzed and catalyzed reaction curves. Label the axis, and the two curves:
Reactants Products + Energy
Draw a reaction coordinate diagram for this reaction as above but add the activation energy, E_{a}, on the appropriate curve in this diagram and label it.
Reactants Products + Energy
Draw a reaction coordinate diagram for this reaction as above but add the activation energy, E_{a}, for the catalyzed reaction on the appropriate curve in this diagram and label it.
Reactants Products + Energy
Draw a reaction coordinate diagram for this reaction as above but this time show the free energy difference. Is G positive or negative?
Reactants Products + Energy
Draw a reaction coordinate diagram for this reaction as above but this time label the reactants, the products and the transition state(s). How many are there on this diagram? How many for each curve?
Reactants Products + Energy
Draw a reaction coordinate diagram for this reaction as above but this time label completely.
Note that heat appears on the product side  the system is giving up heat, therefore H is negative, H =  92.2 kJ
Using Le Châtelier's Principle, predict what will happen to [NH_{3}] if:
 N_{2} is added?
 H_{2} is removed?
 T is decreased?
 Ar is added?
Predict how the equilibrium will shift (right, left, or neither) if:
 V is increased?
What will happen to this reaction if the volume is increased?
What will happen to this reaction if chlorine (Cl_{2}) is added?
2 HI H_{2} + I _{2} K_{eq} = 2.06 x 10^{2} @ 458°C
If both hydrogen and iodine are measured to have concentrations of 0.0135 M each at 458°C, what is the concentration hydrogen iodide?
2 HBr H_{2} + Br_{2}
K_{eq} = 1.5 x 10^{5} @ 1400 K Calculate the concentrations of all species at equilibrium if we start with 0.15 moles each of hydrogen bromide and bromine in a 0.500 L container at 1400 K.
If 0.200 moles of carbon dioxide is placed in a 1.00 L container at 1000 K calculate the concentrations of all species at equilibrium. K_{eq} = 4.5 x 10^{23} @ 1000 K.
Answers 13 & 15
In addition to these exercises you should familiarize yourself with text materials.
© R A Paselk
Last modified 20 November 2009