1. Define activation energy
2. State and explain the result on the reaction rate if each of the following factors is decreased.
Temperature:
Concentration:
Surface Area:
Use the following information to answer question 3
Ethanol is the alcohol found in beer, wine, and whiskey. In the production of ethanol, the starch in barley, grapes, or corn is reacted to form glucose in the presence of enzymes. During the fermentation process, yeast is added to the glucose. The yeast contains enzymes that act as biological catalysts in the reaction of glucose into ethanol and carbon dioxide. The reaction may be represented by the equation
C6H12O6(s) → 2 CO2(g) + 2 C2H5OH(l)
3a. The molar enthalpy of reaction for the fermentation of glucose is _____ kJ/mol.
(show all work)
3b: Draw and energy pathway diagram for the uncatalyzed chemical reaction (assume this
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is a one-step reaction)
Ensure that your graph:
Includes a title
Has labelled axis
Includes reactants and products
Enthalpy Change
Activation Energy
3c: On the same graph draw the catalyzed pathway
Draw the reaction pathway that would result if yeast was added
Label the location of the activated complex on your graph
3d: The enthalpy change for the catalyzed reaction is: __________ kJ/mol
Use the graph below to answer question 4.
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Y
X
ii
i
Ep (kJ)
Reaction Coordinate
4a) Is the reaction shown above endothermic or exothermic?
4b) What do ‘i' and ‘ii’ represent on the graph?
4c) Explain the energy changes that occur at different points during the reaction progress, referring to the conditions needed for a successful reaction, activated complex, as well as potential and kinetic energy.
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Use the information below to answer question 5
Oil refining plants use an exothermic process called cracking to transform ethyne, , into ethene and ethane with the use of a palladium catalyst. This is represented by the reaction shown below:
5a) Draw and energy pathway diagram for the uncatalyzed chemical reaction (assume this is a one-step reaction)
Ensure that your graph:
Includes a title
Has labelled axis
Includes reactants and products
Enthalpy Change
Activation Energy
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5b: State and explain the effect of the palladium catalysts on
Activation Energy:
Yield of Product:
Enthalpy Change:
5c) Draw and energy pathway diagram for the reverse uncatalyzed chemical reaction (assume this is a one-step reaction)
Ensure that your graph:
Includes a title
Has labelled axis
Includes reactants and products
Enthalpy Change
Activation Energy
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5d) Compare the forward and reverse reaction in relation to:
Activation Energy
Magnitude of the Enthalpy Change: