Question

The reaction can be speeded up by using a catalyst that reduces the activation energy. The most popular catalysts are based on iron (Fe) and ruthenium (Ru). The table shows the variation in the concentration of Nz(g) as a function of time for a reaction carried out at 500 °C and 200 atm in the presence 0 0.1 0.2 0.3 0.4 0.5 0.6 of an Fe catalyst:. IN,(e)] (mol/L) 2.00 1.68 1.42 1.19 1.01 0.846 0.710 7. Use these data to determine a) the order of the reaction with respect to N2(g) and b) the value of the overall rate constant k for the synthesis process at the given conditions (graphing method, you will need a spreadsheet program: e.g., Excel, google sheets). NH, In the presence of a solid catalyst, the reaction takes place on the surface of the solid. The following image depicts the reaction path for the synthesis of NH from N2 and Hz over the surface of a ruthenium (Ru) catalyst. The symbol denotes an empty site on the catalyst and X* represents an adsorbed species. 8. Identify the rate-limiting step in the process. 9. Derive the overall rate law for the reaction in the presence of a catalyst. NH Ny 3H *H9* .NZ Na + NH4+ 5H - N: +NH - 14H N NHy 3H- 2NH NH, NH3 10. Discuss the effect on rate of doubling pressure of Nz and Hz. Nye 3H2 2N 3H2 "HEHN+N NH+ + NH3 +2H+ NHg + NH3 +++ 100 400 The rate constant for the synthesis reaction (C) 25 200 300 in the presence of a Fe-based catalysts has been determined at various temperatures. k (5") 3.24 x 10° 2.32 x 10 5.81 x 10- 2.11 x 103 2.64 x 10 The table presents the results: 11. Use the data provided to determine the activation energy in the presence of the Fe-based catalyst (graphing method, you will need a spreadsheet program: e.g., Excel, google sheets). 12. Estimate how many times faster the reaction is in the presence of catalyst compared to the reaction rate in its absence (E.= 325 kJ/mol) at 500°C.