In a study of the decomposition of hydrogen iodide on a gold surface at 150C HI(g)HH2(g)+HI2(g) the following data were obtalned: Minta It is not necessary to graph these data. (1) The observed haif ife for this reaction when the starting concentration is 0.576M is (2) The average rate of disappearance of HI from t=0s to t=521s is Ms1. (3) The average rate of disappearance of HI from t=521 s to t=781 s is Ms. . (4) Based on these date, the rate constant for this order reaction is Ms1 2 more group atiempta remaining