$3$ a Sketch a graph to show the Boltzmann distribution of molecular energies. Label the axes.

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b Define activation energy.

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c Shade an area on the graph to show the number of molecules capable of reacting.

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d Mark on your graph a possible activation energy for the same reaction in the presence of a catalyst.

e Shade an area on the graph to show the additional number of molecules capable of reacting because of the presence of a catalyst.

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f

Draw a second curve on your graph to show the Boltzmann distribution of molecular

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energies at a slightly higher temperature.

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