The gas-phase solid catalyzed reaction, 3H2 + N2 + 2NH3
is carried out over an iron catalyst and proceeds by the following mechanism,
H2 + 2S + 2H. S
N2 + 25 + 2N. S
N. S+H. S + HN. S+S
NH. S+HS H2N. S+S
H2N S + H S + NH4+SS
NH3:S + NH3 + S
Derive a rate law assuming that the dissociative adsorption of N2 is the rate limiting step. You may also assume that the dissociative adsorption of H2 is very weak, since this exothermic reaction is carried out at elevated temperatures.

A3.37-mg sample of protein was chemically digested to convert its nitrogen into ammonia and then diluted to 100.0 ml. then 10.0 ml of this solution was placed in a 50-ml volumetric flask and treated with 5 ml of phenol solution plus 2 ml of sodium hypochlorite solution. the sample was diluted to 50.0 ml, and the absorbance at 625 nm was measured in a 1.00-cm cuvette and found to be 0.486. for reference, a standard solution was prepared from 10.0 mg of nh4cl (molar mass = 53.49 grams/mole) dissolved in 1.00 l of water. then 10.0 ml of this standard was placed in a 50-ml volumetric flask, treated in the same manner as the unknown, and the absorbance found to be 0.323. finally, a reagent blank was prepared using distilled water in place of unknown, it was treated in the same manner as the unknown, and the absorbance found to be 0.076. calculate the weight percent of nitrogen in the protein.