Can I Use Rates Instead of Rate Constants in an Arrhenius Plot?

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To determine the shelf life using the Arrhenius equation, the discussion focuses on the challenge of calculating activation energy (Ea) and the pre-exponential factor (A) due to a lack of known rate constants (k). The user has converted percentage changes into rates at two temperatures: 0.082% per month at 40°C and 0.39% per month at 60°C. The key point is the suggestion to use these rates as effective rate constants for the Arrhenius plot, allowing for the calculation of Ea and A through simultaneous equations. This approach leverages the two data points to solve for the two unknowns, facilitating the analysis of reaction kinetics and shelf life estimation.
mycotheology
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Heres the question:
http://img215.imageshack.us/img215/1185/screenshot5xq.png
Kinetics is probably my weakest area in chemistry so I'm struggling. To find the shelf life, I need to use the Arrhenius equation but I don't know the activation energy Ea or the A constant. So I converted 2 those percentages into rates and got:
At 40C, rate = 0.082 %/month
At 60C, rate = 0.39 %/month
I know that if I plot 1/T vs. lnk, I get an Arrhenius plot and then I can find Ea from the slope and A from the y-intercept but I don't have k. Can I just use the rates that I have instead of k?
 
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You have two data points and two unknowns, that means you should be able to find both solving system of two equations.
 
Can you elaborate on that a bit. Do you mean use simultaenous equations?
 
Yes.
 

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