Chemistry Galvanic Cells Question (1 Viewer)

[Ambility]

https://www.docdroid.net/2NkbVqF/200420syd20grammar20trial20questionspdf.pdf.html

Above is a linked segment of a chemistry trial paper. The section pertains to galvanic cells. I am having particular trouble with question c, the one about constructing a table of standard potentials on page 2. If someone can show me how to do it, that would be great.

Cheers.

 

[leehuan]

Not even a) makes sense to me.

No way all four of the others are, but B IS NOT A REFERENCE CELL. Of course a cell with the same two electrodes will produce 0 voltage.

It's like saying:
Cu(s) -> Cu(2+) + 2e- Eo=-0.34V
Cu(2+) + 2e- -> Cu(s) Eo=+0.34V
Hence Cu(s) + Cu(2+) -> Cu(2+) + Cu(s) EMF = 0V no shit.

This question is nonsensical. It gives no information on anything.

Without knowing how much voltage is produced with B on itself, how can the other 4 simply get derived??

This question simply cannot be done unless by DEFINITION they GAVE that:
B(2+) + 2e- ⇌ B(s) Eo = 0V

 

[Ambility]

Not even a) makes sense to me.

No way all four of the others are, but B IS NOT A REFERENCE CELL. Of course a cell with the same two electrodes will produce 0 voltage.

It's like saying:
Cu(s) -> Cu(2+) + 2e- Eo=-0.34V
Cu(2+) + 2e- -> Cu(s) Eo=+0.34V
Hence Cu(s) + Cu(2+) -> Cu(2+) + Cu(s) EMF = 0V no shit.

This question is nonsensical. It gives no information on anything.

Without knowing how much voltage is produced with B on itself, how can the other 4 simply get derived??

This question simply cannot be done unless by DEFINITION they GAVE that:
B(2+) + 2e- ⇌ B(s) Eo = 0V

That's exactly what I thought. To me, there is not enough information to complete the question. I was hoping someone else on this site would approach it differently, and point out something I'm missing.

For a), I drew a diagram of a cell which would run of the first reaction it gave us. Is that wrong? What exactly do they mean by a "reference cell"?

 

[leehuan]

That's exactly what I thought. To me, there is not enough information to complete the question. I was hoping someone else on this site would approach it differently, and point out something I'm missing.

For a), I drew a diagram of a cell which would run of the first reaction it gave us. Is that wrong? What exactly do they mean by a "reference cell"?

There's nothing wrong with drawing the cell, however there is no such thing as a reference cell here as B can't even be used as a reference cell.

But exactly, without explicitly stating that the half reaction for B produces voltage of 0 (IT IS NOT ASSUMED) it cannot simply be completed.

 

[Queenroot]

pretty stupid tbh

looks something you'd solve with like simultaneous equations lol

 

[leehuan]

pretty stupid tbh

looks something you'd solve with like simultaneous equations lol

Yeah or working backwards if they gave what B was. But it's not that bad in terms of the maths because you'll notice that all of the other four have B in them somewhere.

Ignore the question Ambility. It is extremely stupid

 

[Ambility]

Yeah or working backwards if they gave what B was. But it's not that bad in terms of the maths because you'll notice that all of the other four have B in them somewhere.

Ignore the question Ambility. It is extremely stupid

No worries, thanks for your help.
Although, I might ask again, what exactly is a reference cell? I've never come across the term before.

 

[Queenroot]

No worries, thanks for your help.
Although, I might ask again, what exactly is a reference cell? I've never come across the term before.

Usually it's the Hydrogen half cell, make sure you know this.