guy
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nernst equation
I came across a form of the nernst equation today and it seemed weird.
It was EMF = Eo <b>+</b>0.059/n (log [ion outside of cell]/[ion inside of cell])
I first saw it on this site.
I found it on wikipedia and didn't understand what it was trying to say.
Can someone explain? I never learned this form in high school.
thanks
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bereal511
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I was using the equation last week for an electrochemistry problem. I believe it's simply an equation that calculates the cell voltage by using the
concentrations of the redox participants in the perspective of one of the redox participants.
This helped explain the equation more in terms of use better than a lot of websites I came across.
http://www.science.uwaterloo.ca/~cchieh/cact/c123/nernsteq.h...
If you just go down to the General Nernst Equation section and the Examples section, it helps explain the concept better.
As an adolescent I aspired to lasting fame, I craved factual certainty, and I thirsted for a meaningful vision of human life -- so I became a
scientist. This is like becoming an archbishop so you can meet girls.
-- Matt Cartmill
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guy
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That website only uses the other form of the equation with a minus sign.
Does the nernst equation with the minus calculate the EMF when the concentrations of both the anode and cathode are changed uniformly? And the one
with the PLUS sign calculates when only the concentrations of one electrode are changed?
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guy
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http://www.resonancepub.com/electrochem.htm
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The -sign becomes + if the ion in solution is the oxidised form. But sign of voltages in electrochemistry is a matter of convention.
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What do they mean oxidized form?
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guy
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Finally I figured it out. That site just reversed the equation (flipped the products and reactants) so they changed the signs and messed with my
mind.
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