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Topic: Calculating an equilibrium constant  (Read 808 times)

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Offline vola

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Calculating an equilibrium constant
« on: May 06, 2021, 06:23:00 PM »
 For the same reaction, the standard Gibbs
energy of reaction at 2000K is +135.2 kJmol−1
. Suppose that
steam at 200 kPa is passed through a furnace tube at that
temperature. Calculate the mole fraction of O2 present in the
output gas stream.

i cant find the right result

Offline Borek

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Re: Calculating an equilibrium constant
« Reply #1 on: May 06, 2021, 06:25:07 PM »
Show what you did so far and why you think the answer is incorrect.
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Offline vola

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Re: Calculating an equilibrium constant
« Reply #2 on: May 06, 2021, 06:39:04 PM »
The standard Gibbs energy of reaction for the decomposition of water

H2O(g) --> H2(g) + 1/2 O2(g)

is 135.2 kJ/mol at 2000K.  Suppose that steam at 200 kPa is passed through a furnace tube at 2000K. Calculate the mole fraction of H2(g) in the output gas stream.
sorry, the full question is like that.
 
First I found k=(p/Po)^1/2* alpha3/2 / 2^1/2 ( 1 - alpha )
 using ice table and k value using delta G=RTlnk but I can not understand where should I put the given pressure

Offline mjc123

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Re: Calculating an equilibrium constant
« Reply #3 on: May 07, 2021, 05:31:39 AM »
You didn't forget the minus in ΔG° = -RTlnK, did you?

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