Chemical Forums
Chemistry Forums for Students => Undergraduate General Chemistry Forum => Topic started by: Violet89 on March 25, 2013, 10:10:20 PM
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A first order reaction has an activation energy of 68.1 kJ/mol and a frequency factor (Arrhenius constant) of 1.48 x 1012 sec -1. Calculate the rate constant at 18°C.
K = Ae^(- Ea / RT)
First off, I am confused as to how to enter K = Ae^(- Ea / RT) into my calculator. So, I do it a different way. A quick tutorial on how to do so would be much appreciated though!
My work:
(-68100 / (8.314 * 291.15)) ---> 2nd + LN ---> * (1.48 * 10^12) = 0.896
The correct given answer is 0.883. Why am I slightly off? I entered in those numbers exactly. Did I do something wrong, or does that difference not matter?
I would really appreciate any help or advice! :)
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A first order reaction has an activation energy of 68.1 kJ/mol and a frequency factor (Arrhenius constant) of 1.48 x 1012 sec -1. Calculate the rate constant at 18°C.
K = Ae^(- Ea / RT)
First off, I am confused as to how to enter K = Ae^(- Ea / RT) into my calculator. So, I do it a different way. A quick tutorial on how to do so would be much appreciated though!
My work:
(-68100 / (8.314 * 291.15)) ---> 2nd + LN ---> * (1.48 * 10^12) = 0.896
The correct given answer is 0.883. Why am I slightly off? I entered in those numbers exactly. Did I do something wrong, or does that difference not matter?
I would really appreciate any help or advice! :)
What is the temperature?
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A first order reaction has an activation energy of 68.1 kJ/mol and a frequency factor (Arrhenius constant) of 1.48 x 1012 sec -1. Calculate the rate constant at 18°C.
K = Ae^(- Ea / RT)
First off, I am confused as to how to enter K = Ae^(- Ea / RT) into my calculator. So, I do it a different way. A quick tutorial on how to do so would be much appreciated though!
My work:
(-68100 / (8.314 * 291.15)) ---> 2nd + LN ---> * (1.48 * 10^12) = 0.896
The correct given answer is 0.883. Why am I slightly off? I entered in those numbers exactly. Did I do something wrong, or does that difference not matter?
I would really appreciate any help or advice! :)
What is the temperature?
18°C ---> 291.15 K
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I got 0.896 as well.
0.883 is what you get when you use 273 instead of 273.15 for °C -> K conversion.
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I got 0.896 as well.
0.883 is what you get when you use 273 instead of 273.15 for °C -> K conversion.
Thank you very much.