A catalytic promoter is introduced for the reaction
C(g) → D(g)
Experimental studies provide the following energetic information (all values are relative to the reactants C):
• Uncatalyzed transition state: +180 kJ mol⁻¹
• Catalyzed transition state: +90 kJ mol⁻¹
• Products D: –30 kJ mol⁻¹
Assume that the catalyst does not alter the energies of the reactants or products.
(a) Calculate the activation energy for the uncatalyzed reaction, the activation energy for the catalyzed reaction, and the overall energy change, ΔE. Organize your results in a table.
(b) Sketch a single set of coordinate axes and draw both the catalyzed and uncatalyzed energy profiles on the same graph. Clearly differentiate the two curves and label all critical points, including both transition states, reactants, and products.
(c) Using your graph, describe qualitatively how the presence of the catalyst is expected to influence the reaction rate and explain why the catalyst does not affect the thermodynamic position of equilibrium.