Sciencemadness Discussion Board

I'm trying to do basic electrolysis, where to get electrodes?

Kyryllium - 3-7-2016 at 11:40

Where do i get electrodes? Preferably either platinum or graphite, i'd like to do water electrolysis.

And most importantly, how do i avoid making the explosive H and O combination? forgot the real name


Kyryllium

Trevor9424 - 3-7-2016 at 12:17

Home Science Tools supplies good chemistry equipment for relatively low prices. Search up "electrodes" and you should find copper, carbon, aluminium, and zinc variations. The site also offers wires and battery holders for electrolysis.

http://www.hometrainingtools.com/chemistry

If you want super cheap disposable carbon electrodes, then just take the graphite rods out of regular or mechanical pencils.
Unfortunatetly, if you need platinum electrodes, you'll usually have to find them on a site like Amazon or E-bay.

Remember to search through different stores though and compare quality and price!
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As for avoiding a hydrogen/oxygen mixture (Brown's gas or oxyhydrogen may be the name you're thinking of), just do the experiment in a very well ventilated area (such as outside). It'd be difficult to avoid a hydrogen/oxygen mixture as normal air already has enough oxygen for a hydrogen explosion if there's a ignition source and unless you have a two mouth container in which the two mouths can be closed off from each other by water, you'll be creating the mixture on it's own.

Perhaps you could try U-shaped or V-shaped glass tubing and try to collect the hydrogen by itself with a balloon or something, and the release the hydrogen outside away from an ignition source.

Anyways, good luck.

macckone - 3-7-2016 at 17:31

Hydrogen will go right through most materials. Polymers in general will not contain it. Metals and ceramics work better but hydrogen will migrate through those as well. Although it will be slow enough at standard temperature and pressure. A standard rubber balloon will not work well with hydrogen unless you are producing a lot of it. Heavy rubber tubing will work as escape is inversely proportional to thickness.

Kyryllium - 3-7-2016 at 23:13

Thank you!

Melgar - 5-7-2016 at 09:44

If you want graphite electrodes of any reasonable size, buy a "heavy duty" carbon-zinc 6V lantern battery. They run about $4.50 at Home Depot, and contain four cells, each with a zinc case, full of manganese dioxide with a graphite rod in the center, that's about 1 cm in diameter. You get four of them per battery, and a whole bunch of zinc metal and manganese dioxide. None of these things are harmful or toxic, as long as you make sure to get the "heavy duty" ones. Alkaline batteries use corrosive potassium hydroxide as an electrolyte.

edit: also, if you want to store hydrogen in balloons, make sure to buy balloons specifically rated for helium. Helium has a similar tendency to escape normal balloons.

[Edited on 7/5/16 by Melgar]

macckone - 6-7-2016 at 09:16

Hydrogen will escape from helium rated baloons much faster. Storing it is not easy. That is why labs buy it in high pressure cylinders or make it on demand. The cylinders are not standard carbon steel used for other gases.

MrHomeScientist - 7-7-2016 at 07:55

Another good source for carbon rod electrodes is on eBay - search for "graphite stir rods." They are used for stirring molten metals, usually advertised for the gold and silver crowd. I bought a few of these and they have performed amazingly well as electrodes in my bromine synthesis, hardly deteriorating at all.

aga - 7-7-2016 at 09:12

http://www.ebay.co.uk/itm/5PCS-99-99-Black-Graphite-Electrod...

I got 10 today :)

Melgar - 7-7-2016 at 09:54

Quote: Originally posted by macckone  
Hydrogen will escape from helium rated baloons much faster. Storing it is not easy. That is why labs buy it in high pressure cylinders or make it on demand. The cylinders are not standard carbon steel used for other gases.

Those mylar balloons that look like they're made out of aluminum foil work pretty well. Even the helium-rated balloons work okay to maintain an even hydrogen pressure for a longer period of time than you could otherwise. For instance, to bubble hydrogen for an hour or so, I've used the galinstan+aluminum alloy reacting with water to generate hydrogen, but it can be difficult to control the hydrogen generation rate with much precision. I'd drip water into the mixture, but the chunk of alloy would break apart at some point, and the reaction would speed up a lot more. So I had this hydrogen generator made from an old filtration flask, where I could put a balloon around the neck of it, drip water in one side, and there was a drying tube with an adjustable valve for hydrogen output. The balloon was a nice indicator of when to increase or decrease the water flow rate, and also kept the pressure more or less constant, and easier to control in any case. So even if it did leak some hydrogen, it served its purpose well enough for my needs.

NEMO-Chemistry - 7-7-2016 at 09:59

Quote: Originally posted by aga  
http://www.ebay.co.uk/itm/5PCS-99-99-Black-Graphite-Electrod...

I got 10 today :)

Looks way better than battery ones! silly question but are they the same as the stir ones mentioned above?

Cant go wrong at that price!

aga - 7-7-2016 at 12:17

Quote:
are they the same as the stir ones mentioned above?

I have no idea.

The package arrived today, i opened it and found two plastic bags containing 5 dusty black rods.

Surprisingly none were broken despite having no bubble wrap etc.

Busy tomorrow, so will find out what i can do with them this weekend.

Hopefully do some test-melts with steel ! (~1500C)

NEMO-Chemistry - 7-7-2016 at 13:25

Quote: Originally posted by aga  
Quote:
are they the same as the stir ones mentioned above?

I have no idea.

The package arrived today, i opened it and found two plastic bags containing 5 dusty black rods.

Surprisingly none were broken despite having no bubble wrap etc.

Busy tomorrow, so will find out what i can do with them this weekend.

Hopefully do some test-melts with steel ! (~1500C)


On reflection was a stupid question! at that price is well worth a punt! anything has to be better than the battery ones i have been using, they seem to crumble with little provocation.