yoyoils
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Arrhenius equation help plz
Could someone please help me with this
http://www.chemicalforums.com/index.php?topic=50712.msg188910#msg188910
p.s I apologize for it being a link to another chemistry forum, im just really desperate because this is holding me up a lot of time, if it breaks any
rules or if you don't like it i'll delete this.
[Edited on 20-8-2011 by yoyoils]
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blogfast25
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This really belongs in the 'Beginners section'.
Your question isn't clear though.
Try first to understand the concept of Arrhenius' Lawn (you need to understand Collision Theory for that):
http://en.wikipedia.org/wiki/Arrhenius_equation
Then maybe ask a concise question, one to which an answer exists?
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yoyoils
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I just need to know how to literally use the calculator to get the answers to Arrhenius equation.
question:
k = 1014 * e(-58400 cal/mol /(1.986 cal/K mol * 773 K))
like for example: pressing the following buttons:
[1][.][9][8][6] times [7][7][3] = 1535.178
[STO][1]
[5][8][4][0][0][+-] divided by [RCL][1] = -38.04119131
would someone please tell me what i'm supposed to type in next to answer this with my calculator
the answer is supposedly = 3.01*10-17 but i need to know how to get that
[Edited on 20-8-2011 by yoyoils]
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blogfast25
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Depends on your calculator:
Try:
-38.04119131, SHIFT (or INV), ln x
Or, for more modern calculators:
SHIFT (or INV), ln x, -38.04119131
(in the latter case you may have to put the number between backets ( and ) ) Commas here used to separate keystrokes.
Then multiply with 1014. The answer is 3.0546 x 10<sup>-14</sup>
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yoyoils
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I'm using this calculator now bcuz I found out mines too old http://web2.0calc.com/
I put in: 10^14 * e(-38.04119131) and it = 3.01245472874 which is 3.012 x 10^-3
but I'm still worried if that's not accurate enough because my book states:
k = 10^14 e -58.4/1.53 = 3.03 x 10^-3 s-1
[Edited on 21-8-2011 by yoyoils]
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blogfast25
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Quote: Originally posted by yoyoils | I'm using this calculator now bcuz I found out mines too old http://web2.0calc.com/
I put in: 10^14 * e(-38.04119131) and it = 3.01245472874 which is 3.012 x 10^-3
but I'm still worried if that's not accurate enough because my book states:
k = 10^14 e -58.4/1.53 = 3.03 x 10^-3 s-1
[Edited on 21-8-2011 by yoyoils] |
Which is it (LOL)?
1014 * e(-58400 cal/mol /(1.986 cal/K mol * 773 K)) ??
or
10^14 * e(-58400 cal/mol /(1.986 cal/K mol * 773 K)) ??
Well, 10<sup>14</sup> x e<sup>(-58400 cal/mol /(1.986 cal/K mol * 773 K)</sup> = 3.012 x 10<sup>-3</sup> =
0.003012 s<sup>-1</sup>
At least it's a plausible sounding value...
That web calculator is pretty useless, BTW. It didn't even convert e<sup>-30.04</sup> to the exponential format
(10<sup>somenumber</sup>! That thing is OK for basic calculations but
not much more.
Try the calculator that comes with windows, that's not too bad...
[Edited on 21-8-2011 by blogfast25]
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