Use the following reaction data to determine the general form of the rate law fo
ID: 485284 • Letter: U
Question
Use the following reaction data to determine the general form of the rate law for the reaction A + B --> products. Experiment [A] (M) [B] (M) Rate (1/s) 1 0.050 0.050 0.00077 2 0.025 0.050 0.00039 3 0.050 0.100 0.00077 For the experiment run in question 1, what is the overall order of the reaction? If a reaction is first order and the concentration of the reactant is doubled, what happens to the rate? In this lab, the absorbance measurement is being used instead of concentration for each reactant. Will this affect the results for the orders determined by the reaction? Why or why not?
Explanation / Answer
For the given reaction,
when the concentration of [A] was halved, while keeping [B] constant, the rate halved as well. So reaction is first order with respect to [A]
when the concentration of [B] was doubled, while keeping [A] as constant, the rate remained the same. So the reaction is zero order with respect to [B].
Overall order = first order
For a first order reaction, when concentration is doubled, the rate would also double.
If absorbance is used instead of concentration, no change would be seen. the absorbance would increase with concentration of samples.