Hi,
Basically, I have a graph showing degradation of a organic compound in a form of concentration vs time at different temperatures. A simple exponential function on Excel does more or less fit the curves.
I'm trying to calculate the initial rate of the reaction at t = 0 and then use this in further calculations to calculate the activation energy. I've been differentiating the equation excel gives me at t=0 to find the initial rate. And then the Arrhenius plot.
However, I am not sure about the errors. I know I need to find the errors of the exponential fit so I can carry it forward but I'm not sure how or if there is an easier way! I feel like I'm missing something really obvious here.
Any help would be very much appreciated!
Take log on both sides of the fitting function and do linear regression analysis and then you can calculate standard deviation, chi-quare etc. See, http://www.originlab.com/pdfs/16_CurveFitting.pdf
And http://www.physics.hmc.edu/analysis/fitting.php
First you plot concentration v/s time at different temperatures .Observe the curve the variation is linear then it is zeroth order reaction if it is exponential decrease it is first order reaction then find rate constants at different temperatures. First order reaction take natural log on both sides linearise the equation and find the rate constant . for activation energy calculation use Arrhenius equation calculate the activation energy. Take temperature to be taken in kelvin and gas constant in SI unit. You get activation energy in joule/mole.
- Badges
- Science topic
- Similar topics
- Mathematics
- Applied Mathematics
- Differential Equations