Calculating Q


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204301116
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Calculating Q

Postby 204301116 » Sun Feb 08, 2015 7:32 pm

Is Q always the concentration of the anode over the concentration of the cathode? or does it depend on the situation?

Chem_Mod
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Re: Calculating Q

Postby Chem_Mod » Sun Feb 08, 2015 9:19 pm

Q is the ratio of products to reactants, raised to the power of coefficients. It's the same as the equilibrium expression K, except that K is at equilibrium and Q is at any arbitrary concentrations.

Justin Le 2I
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Joined: Fri Sep 26, 2014 2:02 pm

Re: Calculating Q

Postby Justin Le 2I » Mon Feb 09, 2015 11:40 pm

I think the best way to find Q in problems using the Nerst equation is writing the half reactions and then writing out the full reaction by adding the half reactions. This way, it is clear to you what is happening and you can simply plug in the products and reactants into Q.


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