The decomposition of NH3 to N2 and H2 was studied on two surfaces:
Surface | Ea (kJ/mol) |
W | 163 |
Os | 197 |
Without a catalyst, the activation energy is 335 kJ/mol.
a. Which surface is the better heterogeneous catalyst for the decomposition of NH3? Why?
b. How many times faster is the reaction at 298 K on the W surface compared with the reaction with no catalyst present? Assume that the frequency factor A is the same for each reaction.
c. The decomposition reaction on the two surfaces obeys a rate law of the form
How can you explain the inverse dependence of the rate on the H2 concentration?
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Chapter 11 Solutions
Chemistry: An Atoms First Approach
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