Electrolysis of copper sulphate solution?

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TheConfusedMedic
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Hi, I'm kinda confused on part of the electrolysis of copper sulphate solution (CuSO4)(aq):

Anode: 4OH(-) -----> 2H2O + O2 + 4e(-)
Cathode: Cu(2+) + 2e(-) -----> Cu

I understand the half equation at the cathode, but I'm confused on why so many products are formed at the anode?
Is it just something I have to memorise or is there a simple explanation as to why the products are produced? (This is probably a dumb question haha)
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Mayhem™
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What exam board is this for? I only need to know what ion goes where :lol:
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TheConfusedMedic
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(Original post by Mayhem™)
What exam board is this for? I only need to know what ion goes where :lol:
AQA last topic of C2? (we're so behind arghhhh)
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Mayhem™
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(Original post by surina16)
AQA last topic of C2? (we're so behind arghhhh)
I'm with AQA and I've never seen a question on equations of electrolysis :lolwut:
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TheConfusedMedic
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(Original post by Mayhem™)
I'm with AQA and I've never seen a question on equations of electrolysis :lolwut:
I'm pretty sure it's part of the spec??
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TheConfusedMedic
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Mayhem™
For higher tier: "Candidates should be able to complete andbalance half equations for the reactions occurring at the electrodes during electrolysis."
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Mayhem™
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(Original post by surina16)
Mayhem™
For higher tier: "Candidates should be able to complete andbalance half equations for the reactions occurring at the electrodes during electrolysis."
I don't even look at specs; I just do past papers :lol:
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TheConfusedMedic
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(Original post by Mayhem™)
I don't even look at specs; I just do past papers :lol:
Neither, today was my first time wanted to check that the stuff we're learning is actually relevant :/
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Her._.Majesty
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(Original post by surina16)
Hi, I'm kinda confused on part of the electrolysis of copper sulphate solution (CuSO4)(aq):

Anode: 4OH(-) -----> 2H2O + O2 + 4e(-)
Cathode: Cu(2+) + 2e(-) -----> Cu

I understand the half equation at the cathode, but I'm confused on why so many products are formed at the anode?
Is it just something I have to memorise or is there a simple explanation as to why the products are produced? (This is probably a dumb question haha)

This is deffo on the AQA papers. Just remember that the Anodes positive, The Cathode is negative then remember the products. There's no explanation, just gotta learn it
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TheConfusedMedic
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(Original post by Her._.Majesty)
This is deffo on the AQA papers. Just remember that the Anodes positive, The Cathode is negative then remember the products. There's no explanation, just gotta learn it
Ah, that's annoying tbh, but thanks
Yeah we have the acronym PANIC to remember it
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danr2
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you need to know which procduct will be formed as well
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username2337813
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(Original post by surina16)
Hi, I'm kinda confused on part of the electrolysis of copper sulphate solution (CuSO4)(aq):

Anode: 4OH(-) -----> 2H2O + O2 + 4e(-)
Cathode: Cu(2+) + 2e(-) -----> Cu

I understand the half equation at the cathode, but I'm confused on why so many products are formed at the anode?
Is it just something I have to memorise or is there a simple explanation as to why the products are produced? (This is probably a dumb question haha)
During electrolysis:the cathode gets coated with copper. bubbles of oxygen are given off at the anode As the copper ions are discharged as copper atoms at the cathode, the blue colour of the solution gradually fades and an oxidation reaction occurs which is the 4e- (electron loss).
The negative sulphate ions (SO42-) or the traces of hydroxide ions (OH–) are attracted to the positive electrode. But the sulfate ion is too stable and nothing happens. Instead either hydroxide ions or water molecules are discharged and oxidised to form oxygen.
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danr2
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(Original post by hxfsxh)
During electrolysis:the cathode gets coated with copper. bubbles of oxygen are given off at the anode As the copper ions are discharged as copper atoms at the cathode, the blue colour of the solution gradually fades and an oxidation reaction occurs which is the 4e- (electron loss).
The negative sulphate ions (SO42-) or the traces of hydroxide ions (OH–) are attracted to the positive electrode. But the sulfate ion is too stable and nothing happens. Instead either hydroxide ions or water molecules are discharged and oxidised to form oxygen.
if the negative ion is not part of the halides then oxygen is formed
if the positive ion is above hydrogen in the reactivity series then hydrogen is formed

this applies to substances in aqueous solution ONLY.this rule doesn't apply to molten substances

just an additional info
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