Thread: How do you determine a rate law given time of the reaction and absorbance and temperature?

I am doing a lab on determining rate law and activation energy. In each reaction i kept concentration the same but tested it at different temperatures. The reaction mixture was placed in a colorimeter to measure absorbance. The data I have is time, absorbance, % transmission, and temperature. I have to graph my data to determine the rate law, integrated rata law and so on, how do I graph this?

I can't answer that question entirely without more information, but I can start you in the right direction. The rate law expresses the way that reactants turn into products as a function of time. The absorbance that you see is proportional to either the concentration of the reactants or products. In a simple case, you would use Beer's Law to calculate the concentration from the absorbance, assuming that you know the path length of the sample and molecular extinction coefficient (also known as molecular absorbtivity constant) of the absorbing molecule(s). For the rest of your problem, I suggest looking here: http://en.wikipedia.org/wiki/Rate_law or in your chemistry book.