Electrochem. Check

[D3a2N1]

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I'm just trying to make sure I have this correct:

When balancing a redox reaction, you need to make sure the molar ratio of electrons is equal for both half reactions. For example, if the reduction half rxn equation has 2e and the oxidation half rxn equation has simply e, you need to multiply the oxidation half rxn equation by 2 in order to balance the two half rxns.

However, for calculating the electric potential of a electrochemical cell its simply the reduction plus the oxidation potential (they are almost always written as the reduction potential, so it would be the largest + reduction potential added to the opposite of smallest reduction potential, so the Ecell is ultimately positive). This does not involve any balancing like in the redox rxns....correct?

 

[premedmind]

I'm pretty sure that cell potential must always be positive (if its not the reaction is not spontaneous and won't proceed), and there is no balancing of cell potential equations.

Ecell = cathode - anode,

the electrons lost in oxidation must be gained in reduction

Someone back me up here - im calling upon 4 months old knowledge.thats what I can quickly get of the top of my head.

 

[sushi320]

its not always positive, electrolytic cells are not spontaneous. And in that type of cell, the anode is positive and cathode neg.