This is a stupid question but..... (1 Viewer)

[Prawnchip]

Why is there negative potential? Like on the sheet with standard potentials, why are there negatives?

 

[Queenroot]

Why is there negative potential? Like on the sheet with standard potentials, why are there negatives?

Awkward Lol.
The more negative a standard potential is, the more likely it is oxidised (in comparison to the other substance of course).

 

[Prawnchip]

Awkward Lol.
The more negative a standard potential is, the more likely it is oxidised (in comparison to the other substance of course).

I don't get you...

 

[Queenroot]

I don't get you...

The oxidation potential decreases as you move down the list of standard potentials.

 

[Prawnchip]

The oxidation potential decreases as you move down the list of standard potentials.

So does the negative sign mean nothing more except to tell you that the oxidation potential decreases? Cos I thought potential difference was like A - B

 

[girlworld_club]

The numbers in the table are the reduction potentials. The more positive means it is more likely to be reduced. If you flip the reduction potentials around you get the oxidation potentials. Again the more positive, the more likely it is to be oxidised. On a reduction potential chart, The more negative it gets confers to it going "further and further" away from wanting to be reduced.

 

[Chubbeh]

I think they're all relative to H's reduction potential (0.00V). Random guess though. So anything above H (ie negative) would have a greater oxidising potential, and anything lower would have a greater reduction potential.

 

[AnimeX]

I think they're all relative to H's reduction potential (0.00V). Random guess though. So anything above H (ie negative) would have a greater oxidising potential, and anything lower would have a greater reduction potential.

yup, they're relative to hydrogen

 

[someth1ng]

I think they're all relative to H's reduction potential (0.00V). Random guess though. So anything above H (ie negative) would have a greater oxidising potential, and anything lower would have a greater reduction potential.

This is correct, all other explanations here are wrong.

If that question was asked in the HSC, everyone else in this thread would get 0.

 

[someth1ng]

I don't remember learning about H+ reduction potential in class, would you care to explain?

Simply, all standard potentials are measured against a standard hydrogen cell.

 

[Queenroot]

I don't remember learning about H+ reduction potential in class, would you care to explain?

How could you not learn it?
Hydrogen by itself does not produce a voltage. Hence, the other standard potentials were measured against hydrogen, which changed the voltage of the overall cell from 0 to whatever.


I would not get 0. Lol, I remember this because I had an assignment on galvanic/electrolytic cells and I'm the only one who had that explanation in the assignment and got 94%. Yay.

 

[someth1ng]

How could you not learn it?
Hydrogen by itself does not produce a voltage. Hence, the other standard potentials were measured against hydrogen, which changed the voltage of the overall cell from 0 to whatever.


I would not get 0. Lol, I remember this because I had an assignment on galvanic/electrolytic cells and I'm the only one who had that explanation in the assignment and got 94%. Yay.

Well, get a proper teacher then.

Also, saying that hydrogen doesn't produce a potential is wrong - it's only convention to say that it's 0.00V to measure against it...it's just a standard, that's all.

In addition, the question was "why is there negative potential" - not "what causes negative potential" or similar.

 

[Queenroot]

Well, get a proper teacher then.

Also, saying that hydrogen doesn't produce a potential is wrong - it's only convention to say that it's 0.00V to measure against it...it's just a standard, that's all.

In addition, the question was "why is there negative potential" - not "what causes negative potential" or similar.

Yeah, I get it.
And because it was a research assignment, but nobody else desired to go into that much depth.