equilibruim based on enthalpy

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Nahelly Alfaro-2C
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Joined: Wed Nov 15, 2017 3:04 am

equilibruim based on enthalpy

Postby Nahelly Alfaro-2C » Sun Feb 24, 2019 8:14 pm

How can you determine the shift in the equilibrium of a chemical reaction when only given the change of enthalpy of the reaction?

105114680
Posts: 60
Joined: Fri Sep 28, 2018 12:23 am

Re: equilibruim based on enthalpy

Postby 105114680 » Sun Feb 24, 2019 8:18 pm

If the change in enthalpy is positive the reaction is endothermic (it requires heat to form products) and so raising the temperature will cause the equilibrium to shift toward the right (i.e., more product will be formed since more heat is available). If the change in enthalpy is negative the reaction is exothermic (it gives off heat) and so adding heat will favor the formation of reactants and the equilibrium will shift to the left. Hope this helps!

kateminden
Posts: 63
Joined: Fri Sep 28, 2018 12:24 am

Re: equilibruim based on enthalpy

Postby kateminden » Sun Feb 24, 2019 11:33 pm

105114680 wrote:If the change in enthalpy is positive the reaction is endothermic (it requires heat to form products) and so raising the temperature will cause the equilibrium to shift toward the right (i.e., more product will be formed since more heat is available). If the change in enthalpy is negative the reaction is exothermic (it gives off heat) and so adding heat will favor the formation of reactants and the equilibrium will shift to the left. Hope this helps!


This was so helpful! I was confused by this too, but now it actually makes sense, so thanks :)

Alysa Rallistan 2G
Posts: 32
Joined: Thu Jan 17, 2019 12:16 am

Re: equilibruim based on enthalpy

Postby Alysa Rallistan 2G » Mon Mar 11, 2019 11:20 pm

Looking at the change in enthalpy alone won't be enough information to determine the equilibrium of a reaction or not but the sign of it does tell you whether heat is a reactant or product and from there you can follow the steps mentioned above.


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