Penicillin G reacts with hydroxylamine (NO2OH) to form hydroxamic acid, which produces a colored complex with iron(III).
To determine the overall reaction order, equal concentrations of penicillin and NH2OH were mixed together in a 250-mL flask [J. Chem. Educ., 49,
539 (1972)]. Samples were withdrawn every 10 minutes and added to a solution containing
iron(III) chloride. With the aid of a colorimeter, the concentration of the colored
complex, and hence the concentration of hydroxamic acid, was obtained as a function
of time. The absorbance shown in the table below is directly proportional to the
hydroxamic acid concentration.
(a) Use the nonlinear least squares (i.e., regression) and
one other technique to determine the reaction order,, and specific
reaction rate, k. (b) What experimental conditions would you suggest if you were to obtain more
data?