Standard Reduction Potentials

[SSerenity]

I came across this table in an MCAT question. They call these potentials Standard Potentials, not Standard Reduction Potentials.

I was pretty sure when given a Standard Reduction Potential, it does not matter how the reaction is written. It always represents:
X^+ + e^- = X

In this table some of them are written backwards. I know permanganate must be the strongest oxidant. This means the standard reduction potential for Na+ MUST be negative, not positive. So some of these are oxidation potentials and other reduction potentials?

I cross referenced this in some GS exams. They always use Reduction potentials, but they don't explicitly call them reduction potentials. Instead they call them "E^o" (E-not).

Is it safe to assume any E-not value is always going to be a Standard Reduction Potential?

This is confusing because I've seen questions where they write the reaction like an oxidation, but the E-not value refers to the standard reduction potential.

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[randymoss]

I came across this table in an MCAT question. They call these potentials Standard Potentials, not Standard Reduction Potentials.

I was pretty sure when given a Standard Reduction Potential, it does not matter how the reaction is written. It always represents:
X^+ + e^- = X

In this table some of them are written backwards. I know permanganate must be the strongest oxidant. This means the standard reduction potential for Na+ MUST be negative, not positive. So some of these are oxidation potentials and other reduction potentials?

I cross referenced this in some GS exams. They always use Reduction potentials, but they don't explicitly call them reduction potentials. Instead they call them "E^o" (E-not).

Is it safe to assume any E-not value is always going to be a Standard Reduction Potential?

This is confusing because I've seen questions where they write the reaction like an oxidation, but the E-not value refers to the standard reduction potential.

If they write a reaction as an oxidation it's just the opposite sign of the reduction potential. It doesn't matter how it's written in a table. If something is gaining electrons, it's being reduced and is therefore showing a reduction potential. If it's losing electrons (electrons on right side of equation) it's being oxidized and it'a the oxidation potential.

Na and Ni show oxidation potentials. Just reverse the sign (+ to -) to get their reduction potentials.

 

[SSerenity]

Not quite the question I had in mind, but thank you!

 

[randymoss]

Not quite the question I had in mind, but thank you!

Sorry, what's your question?

 

[athockey7]

im confused when you simply add and when you substract when you are combining two half reactions

E = Ecat - Eanode

in this case ^ you take the number just as they are if they are both reduction potentials and then substract them.... or if they are both oxidation potentials

but you can simply add the two when you have accounted for each and one is the reduction potential and the other is the oxidation potential?

sorry i dont even know what i wrote which shows my weakness in this area, but would appreciate help

also didnt mean to steal but thought my ? could add to OP
instead of a new thread