An exception to Keq>1.0?

[pfaction]

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Unless I'm mistaken, Keq>1 features more products than reactants, by definition. So all things considered, a Keq of >1, like acids and bases, would mean more conjugates than undisassociated.

So I'm reading TBR GChem Ch. 10 on galvanic, where it says: for an Oxid-Red'n of Keq>1, there is more reactants than products and the cell voltage is greater than the standard cell voltage.

Huh? For an oxidation-reduction I would expect Keq >1 to mean more products than reactants, and the voltage to be decreased based on this?!

 

[pm1]

Unless I'm mistaken, Keq>1 features more products than reactants, by definition. So all things considered, a Keq of >1, like acids and bases, would mean more conjugates than undisassociated.

So I'm reading TBR GChem Ch. 10 on galvanic, where it says: for an Oxid-Red'n of Keq>1, there is more reactants than products and the cell voltage is greater than the standard cell voltage.

Huh? For an oxidation-reduction I would expect Keq >1 to mean more products than reactants, and the voltage to be decreased based on this?!

this is just a guess.. but couldn't it be that when in EQUILIBRIUM the products are favored over reaction, but the cell hasn't reached equilibrium yet? Q < 1 ?

 

[MedPR]

Unless I'm mistaken, Keq>1 features more products than reactants, by definition. So all things considered, a Keq of >1, like acids and bases, would mean more conjugates than undisassociated.

So I'm reading TBR GChem Ch. 10 on galvanic, where it says: for an Oxid-Red'n of Keq>1, there is more reactants than products and the cell voltage is greater than the standard cell voltage.

Huh? For an oxidation-reduction I would expect Keq >1 to mean more products than reactants, and the voltage to be decreased based on this?!

If the reaction has a Keq>1 and the galvanic cell has more products than reactants, then there would be no reaction. Once something reaches equilibrium, nothing happens. So since galvanic cell = spontaneous cell, there must be more reactants than products if anything is to happen for a reaction with Keq>1.

 

[MrNeuro]

Keq is just the [prod]/[reac] the keq needs to be greater than 1 so that the reaction will shift to more prod than reactants (in a galvanic cell). You can imagine that if a galvanic cell has a keq < 1 the rxn won't shift to more products unless you mess with the equilibrium either by shifting via le chatlier or altering via a temp change. When a galvanic cell first is setup its NOT at equilibrium. But rather a Q of [reactants]>[products] that then shifts to Keq if the keq is lower then you'll produce less product.

Make sense?

 

[gettheleadout]

OP, all they're saying is that the reaction that occurs in the cell has a Keq > 1, but that because the cell functions, Q is currently less than 1 (meaning the reactant/product concentrations are not yet at equilibrium, thus a reaction can occur and the cell can function.)

Edit: Yeah, what MrNeuro said. 😛

 

[pfaction]

I still don't get it. Okay, the Keq>1. Oh wait, this just means it's favorable, has nothing to do with the actual concentrations yet, right? It's like having 100mL of Na and 100mL of Cl, with a Keq>1 it'll go towards NaCl. Braindied!