Voltaic cell and electrolysis, simoultaneously ?

[Externet]

Hi all.

 

A voltaic cell with a carbon rod and aluminium rod electrodes generates some potential in a container with seawater.

 

If that voltage is applied to other two platinum electrodes in the same electrolyte in the same container, will they generate some gases ?

[Mr Skeptic]

Considering that aluminum is made by electrolysis with carbon (graphite) rods, wouldn't it just be more efficient to use the original electricity to do electrolysis rather than add the extra step with aluminum and carbon that later gets reversed?

[Externet]

Thanks for responding. I know too little about this...

 

The intention is to electrolytically produce any gases from seawater using voltage generated by electrodes immersed in it as a voltaic cell; perhaps carbon and magnesium.

 

Or, if two dissimilar (connected?) elements immersed in seawater can themselves generate bubbling.

[Mr Skeptic]

In any case, it would be an overall negative to refine a material to then consume it to make hydrogen. Why not go directly? You can produce hydrogen from combining carbon and oxygen.

[Externet]

Thanks. Nothing to do with anything, I have no interest in refining nor hydrogen as itself.

 

I want to produce gases of any kind from seawater electrolysis to create buoyancy that will bring a device in the bottom of the sea to surface after a period of time.

Powered by a seawater voltaic cell, probably graphite and magnesium.

 

The whatever gases Cl, H, O will have no use other than the volume they grow up to in a bladder.

 

Or, if any easily obtainable material produces gas in contact with seawater.

Edited June 23, 2008 by Externet
wording

[Mr Skeptic]

Oh, I thought this was related to using the hydrogen later as a fuel... Most metals will react with acid and release hydrogen gas. Zinc and hydrochloric acid is a good one. Most carbonates will react with acid to release CO2, but under pressure much of that will dissolve. Baking powder or limestone would work for that. For a time-release mechanism, you can either use a single large chunk of metal, or separate the metal from the acid by a material that dissolves slowly in the acid.