Rate constant help for this reaction please

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SUMMARY

This discussion focuses on the correct formulation of rate constants for chemical reactions, specifically reactions 1 to 12 using the Arrhenius equation. The user expresses confusion regarding the application of the Arrhenius form for rate constants 7 to 12, particularly in evaluating temperature and the preexponential factor. Key corrections include the need to use 220.5 in the exponential term instead of 158.6, and clarification that the variable ρb is 1700. Additionally, the activation energy for reaction 6 is confirmed as -30.6 kJ/mol, which raises questions about its classification as a simple Arrhenius reaction.

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  • Familiarity with rate constants in chemical kinetics
  • Knowledge of activation energy concepts
  • Basic thermodynamic principles, including the gas constant (R)
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maistral
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TL;DR
Deciphering old journal's rate constant notation.
So I was looking for some rate constants for a certain reaction and I found these:

rateconstants.png


So I wanted to try them. The problem is, I have no idea how to correctly write the rate constants. Reactions number 1 to 6 is a no-brainer as it's simple Arrhenius. My problem is for rate constants 7 to 12. I am aware of evaluating T at Tr, the problem is I have no idea how to write the entire Arrhenius form and I am somehow unable to wrap my head around it. Can someone give me an idea how? Thanks.

EDIT: I'm guessing, but are these correct? I follow the equation then I compute the preexponential? For rate constant 7, this:
guess1.png


and for rate constant 12, this:
guess2.png
 
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What is the number 1700? Is that ρb? do you know that from somewhere? What else do you know?
Your denominator should have 220.5 in the exponential term, not 158.6. (And that means you should us a value of R in kJ/mol/k.)
Is the activation energy of -30.6 kJ/mol for reaction 6 a typo for 30.6? If not, then it's not "simple Arrhenius"!
With these caveats, I think you are on the right lines.
 
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Ah, yes. The variable ρb is 1700. And yeah, 158.6 is a typo, and it should be 220.5. Also, for reaction 6 apparently it's really -30.6 as stated by the paper.

Thanks for assuring me that I am somewhat 'okay'. I really appreciate it as I am really confused with this.
 

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