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Two questions regarding electrolysis. Answered

Okay; two questions regarding electrolysis. What should i use as an electrolyte? When I used salt, I got Hydrogen and Chlorine, and I want Hydrogen and Oxygen. Next, What should I use for my anode and cathode? I've heard of carbon rods and titanium rods, but i don't know where to get them from.?


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Jack A Lopez
Jack A Lopez

Best Answer 10 years ago

Regarding carbon rods, these can be found in old zinc-carbon batteries (sizes AA, C, D) See this ible by NurdRage:

Also, on the same topic, plain titanium is vulnerable to passivization if used as an anode. Another NurdRage video"
Passivization of Titanium Metal

Regarding what electrolyte to use, I'd try dilute sulfuric acid, or maybe dilute sodium hydroxide, or maybe sodium carbonate, or sodium bicarbonate.

The sort of reasoning involved in picking an electrolyte is to choose one that has ions which are unlikely to "want to" leave the water, either by plating as a solid (typically on the cathode), or as a gas (typically on the anode), or by forming some sort of insoluble precipitate.

For example:  Na+ ions  don't want to leave the water, even if they did plate out into small amounts of sodium metal, that metal would instantly react with the water, and you'd be back to dissolved ions again.

Similarly for SO4-2, and HSO4-, these ions don't want to leave the water. Even if you did manage to create some SO3 gas at the anode, it would quickly react with the water before it could bubble out.


10 years ago

If you're using tap water it's got enough impurities to use just as is. Or you can add a small amount of sulfuric acid to improve conductivity.