Dry Cell

[Primarygun]

What happens if I use Iron(III) sulphate as electrolyte with silver electrode and gold electrode? Can this be an electrolysis set-up?

I guess Iron(II) sulphate and hydrogen gas are the product.

By the way, how does a lithium cell work?

 

 

why the standard reduction potential for

2H+(aq)+2e----> H2(g) is 0?

That implies H+ is not reactive.

[Mendelejev]

Lithium cells are very small cells. Perfect for pacemakers ! The cathode is an I2-complex that will reduce to I-. The anode is Li that will be oxidized to Li+.

 

Li+ + e- -> Li E° = - 3,03 V

I2 + 2e- -> 2 I- E° = + 0,54 V

 

=> 2 Li + I2 -> 2 Li+ + 2 I-

 

The seperation between the anode and the cathode consists of LiI-crystals. Li+ can pass but becouse of the large inner resistance there is no big amount of electricity that can flow threw the cell. For this reason lithium cells will work longer than other cells. Li also has the smallest relative atomic mass of the anode metals, so it can provide the most electrons per mass. This also results in a small weight. But it's quite expensive to produce Li cells out of LiCl-electrolysis. That's why we only use them for some specific applications. (for example pace makers)

[Primarygun]

Lithium chloride is the electrolyte?

What things have a more negative value of SRP than Li?

[budullewraagh]

nothing. lithium is the most active metal with the most negative reduction potential

[YT2095]

What happens if I use Iron(III) sulphate as electrolyte with silver electrode and gold electrode? Can this be an electrolysis set-up?

I guess Iron(II) sulphate and hydrogen gas are the product.

 

you`de get one of your electrodes plated with Iron metal for a while, then the other electrode will form an insoluble coating of either gold or silver sulphate and the reaction would stop as the resistance will be too high, and the iron metal would re-dissolve

[Primarygun]

How about if I use Iron(II) sulphate instead?

I guess H2 at +ve and Iron(III) ions gathering at -ve

[YT2095]

ANY type of sulphate will create the resistive barrier coating on the gold or silver electrodes

[budullewraagh]

eh, there are soluble sulfates and sulfate complexes/hydrates

[Borek]

why the standard reduction potential for

2H+(aq)+2e----> H2(g) is 0?

That implies H+ is not reactive.

 

No. It is zero just because it was selected as a reference.

 

Best' date='

Borek

--

Chemical calculators for labs and education

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[YT2095]

eh, there are soluble sulfates and sulfate complexes/hydrates

yes of course there are, that`s not in dispute. but Silver or Gold sulphates are not very soluble or conductive and thus will cause a ceasation in the reaction.

[Primarygun]

How about if I use a porous barrier to separate the two region of the same solutions?

[YT2095]

same thing, you`de still be having to clean your electrodes off every 30 seconds, I`ve tried this before, it sucks!

[Primarygun]

I read a book. If a the two solutions are connected by a salt bridge, assume both solutions are Iron(II) sulphate, electrodes are the above ones, the solution turns yellow.

[YT2095]

why dont you just use carbon electrodes and your porous barrier?

 

saves alot of messing about!

[akcapr]

and is probly alot cheaper