Sep 4, 2009
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For an exothermic reaction at 100 C , the equilibrium concentration of the products equals the equilibrium concentration of the reactants. What is true at 25 C?

A. Keq > 1 : [Products]> [Reactants]
b. Keq > 1 : [Products]< [Reactants]
c.Keq < 1 : [Products] > [Reactants]
d.Keq < 1 : [Products] <[Reactants]

ok , I 'm a little confused here. Answer is A

How is it possible to have a 1/1 ratio of Keq when heat is added into the system. Also, in this case how do we know which side is favored to remove excess heat. Is the system going to favor products ( to cool off the effect of heat) or would it prefer to go to the left and favor reactants?

I understand that if the products are favored to give release heat into the system, then if we cool this system, we would want to go to the products side (and thus release more heat). which would make the Equil K to be greater than 1 as more products are made. I just dont understand HOW you can tell that heat is given off in the forward direction. Please help!!!
 

RogueUnicorn

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Jul 15, 2009
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heat, temperature, none of this matters. they gave you a Keq for a given reaction at a given condition. what does Keq mean? that's what they're trying to get at. a nice question imo.
 

badmintondr

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Dec 10, 2009
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Just wondering Bleargh, you said heat/temp don't matter so would I be wrong in using the logic that this is an exothermic reaction saying heat is on the right side and decreasing heat results in more product. Thus resulting in Keq>1 because Keq is products over reactants?

I thought I reasoned it out right but if you say heat/temperature is not important then I know I must be wrong for sure cause Bleargh is never wrong lol.
 

RogueUnicorn

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Just wondering Bleargh, you said heat/temp don't matter so would I be wrong in using the logic that this is an exothermic reaction saying heat is on the right side and decreasing heat results in more product. Thus resulting in Keq>1 because Keq is products over reactants?

I thought I reasoned it out right but if you say heat/temperature is not important then I know I must be wrong for sure cause Bleargh is never wrong lol.
:laugh: if only.. ironically i misread the question. haha. so to explain - it's an exothermic reaction so heat is released. at 100C, the products and reactants are the same. as you astutely note, decreasing heat means more product, which means Keq>1. good job.