Electro Chemistry

[SwissGold]

Hello,
Let's say in a electrolytic bag made from a special metal which is not reactive, we add differents metal:
Tin, Copper, Antimoni, Lead, Titanum, Iron, Steel. This basket is our anode.
Then we apply on cathode 20 A/m2.
The electrolyte is H2SO4. As lead is not that soluble in H2SO4, it should maybe dont react, no? What about the other metal? What would goes in theory to the cathode? Do we care about Voltage?

 

[butcher]

Electrolysis or using electricity to force chemical reactions that may not occur otherwise, for example, your car battery uses lead and dilute H2SO4 and here the lead reacts to the applied electrical forces.

So if you applied voltage you could force electrons to move (that may not have moved on their own otherwise), dissolving the metals at the anode into salts of those metals and as the ions migrate to the cathode reducing the ions of these metals at the cathode back into atoms of the metals with a full shell of electrons.

 

[SwissGold]

Electrolysis or using electricity to force chemical reactions that may not occur otherwise, for example, your car battery uses lead and dilute H2SO4 and here the lead reacts to the applied electrical forces.

So if you applied voltage you could force electrons to move (that may not have moved on their own otherwise), dissolving the metals at the anode into salts of those metals and as the ions migrate to the cathode reducing the ions of these metals at the cathode back into atoms of the metals with a full shell of electrons.

I may was confusing. I know chemically what happen. What i wanted to know is which one will goes to cathode and which will stay in the anode. For sure the Lead will stay, or have very low concentration in cathode, as it cant dissolve in H2SO4. But what about other metals...

 

[g_axelsson]

It depends...

... but to me it sounds like a mess. Electrolytic processes works differently depending on electrolyte composition, cathode material, current density, temperature, pH, agitation, cell geometry, star sign... and probably a number of factors we don't know just to throw us off.

Even simple systems can be tricky to get it working. It's fascinating to see how simple a silver cell is and how easy it is to run it, compared to metals like iron or zinc.
You can electrowin zinc out of a zinc sulfate solution if you have a pure zinc cathode, but if there is a bit of iron in solution then it will plate out instead of zinc and on that iron water will be converted into hydrogen instead of zinc plated out, killing the process.

In a sulfuric acid cell you can rip gold off plating while zinc, iron, aluminium or copper doesn't react at all.

Electrochemistry is a messy area and those that master it are gods. The simple pictures given in chemistry books is just an introduction into ideal solutions, the real world is a lot more complicated than that.

The general answer is that more reactive metals dissolves faster than less reactive, but that's just the beginning of it.

Göran

 

[kurtak]

It depends...

... but to me it sounds like a mess. Electrolytic processes works differently depending on electrolyte composition, cathode material, current density, temperature, pH, agitation, cell geometry, star sign... and probably a number of factors we don't know just to throw us off.

Even simple systems can be tricky to get it working. It's fascinating to see how simple a silver cell is and how easy it is to run it, compared to metals like iron or zinc.
You can electrowin zinc out of a zinc sulfate solution if you have a pure zinc cathode, but if there is a bit of iron in solution then it will plate out instead of zinc and on that iron water will be converted into hydrogen instead of zinc plated out, killing the process.

In a sulfuric acid cell you can rip gold off plating while zinc, iron, aluminium or copper doesn't react at all.

Electrochemistry is a messy area and those that master it are gods. The simple pictures given in chemistry books is just an introduction into ideal solutions, the real world is a lot more complicated than that.

The general answer is that more reactive metals dissolves faster than less reactive, but that's just the beginning of it.

Göran

Which why just about every time I think I am really smart - I end up finding out just how dumb I really am :shock: :lol: :twisted:

Kurt

 

[SwissGold]

It depends...

... but to me it sounds like a mess. Electrolytic processes works differently depending on electrolyte composition, cathode material, current density, temperature, pH, agitation, cell geometry, star sign... and probably a number of factors we don't know just to throw us off.

Even simple systems can be tricky to get it working. It's fascinating to see how simple a silver cell is and how easy it is to run it, compared to metals like iron or zinc.
You can electrowin zinc out of a zinc sulfate solution if you have a pure zinc cathode, but if there is a bit of iron in solution then it will plate out instead of zinc and on that iron water will be converted into hydrogen instead of zinc plated out, killing the process.

In a sulfuric acid cell you can rip gold off plating while zinc, iron, aluminium or copper doesn't react at all.

Electrochemistry is a messy area and those that master it are gods. The simple pictures given in chemistry books is just an introduction into ideal solutions, the real world is a lot more complicated than that.

The general answer is that more reactive metals dissolves faster than less reactive, but that's just the beginning of it.

Göran

nice reply...i will let you know after a try or two...i will recive soon my alloy

 

[Lino1406]

If I understand the goal - theorethical study? then copper goes first, titanium goes last according to electrochemical series.