Making hydrogen

MisterSteve124 · Thu Aug 30, 2007 1:33 pm

So today I'm going to start making an electrolysis machine so I can make some hydrogen. I know that some of you have probably done it before. I read that the water gets hot when you start putting the current through it. Is there anyway to stop this or atleast slow it down. I was thinking you could probably add some ice to the water to make it cold which could give you more time until you have to shut it off. And how will I know when I need to stop if it gets too hot? Thanks

paaiyan · Thu Aug 30, 2007 1:45 pm

It doesn't really matter too much if it gets warm. Just add some ice and some more of your electrolyte. When it starts boiling, you might want to stop for a bit.

Just kidding, when you ccan feel a significant amount of warmth without actually touching it, just give it a break for a bit.

MisterSteve124 · Thu Aug 30, 2007 1:50 pm

ok should I use baking soda or salt? Doesn't salt make chlorine gas? And one more thing won't one electrode be making oxygen and one be making hydrogen? So then it wouldn't really be pure hydrogen it would be a mixture. Can I seperate the electrodes and just get the hydrogen? Or do they have to be close?

paaiyan · Thu Aug 30, 2007 1:54 pm

I'm trying to remember, if you use sodium bicarbonate, one will produce hydrogen and one oxygen, you can collect them seperately, it's safer that way. DO NOT use salt. Salt makes chlorine in this process, and chlorine is bad. The electrodes may get some buildup on them after a while, just stop every now and then and clean that off.

potatoflinger · Thu Aug 30, 2007 1:57 pm

You can separate the electrodes, and have a tube above each to collect the gas. If you do that, it won't be a mix, and you will be able to tell which is which because there will be twice as much hydrogen as oxygen (H2O). You should use baking soda because I have hears that salt can make chlorine gas, but I'm not positive.

paaiyan · Thu Aug 30, 2007 1:59 pm

I know salt makes chlorine. And it is safer to collect the gasses seperately. If they're mixed, they tend to ignite very easily. And the reaction is extremely powerful.

MisterSteve124 · Thu Aug 30, 2007 2:09 pm

ok do you know which electrode will create which gas?

paaiyan · Thu Aug 30, 2007 2:18 pm

The negative electrode should make hydrogen, if I remember correctly.

beebs111 · Thu Aug 30, 2007 11:38 pm

you do remember correctly, i enjoy igniting ballons of the mix, it is a prefect mix for detonation(not technically) and makes a fair sized boom

jimmy101 · Fri Aug 31, 2007 12:50 pm

The elecrode that produces hydrogen will produce twice the volume of gas as the elctrode that produces oxygen. For example, if you use a setup like;

The gas level in the tube containing hydrgen will be twice the amount in the other tube. (In the drawing the test tubes are drawn down way to far for efficient operation of the cell.)

Or, the gas that burns is hydrogen, the gas that makes something else burn like crazy is oxygen.

Or, the boring old "oygen is formed at the positive terminal, hydrogen at the negative".

Epsom Salts (Magnesium sulfate hexa(?)hydrate, available at drug and grocery stores) is often used as the electrolyte since it doesn't create toxic gases like you will get with sodium chloride (table salt).

Lye (sodium or pottasium hydroxide, available in some kinds of drain cleaners) also works well. But, concentrated hydroxide solutions are corrosive and will burn skin. Many drain cleaners also contain aluminum shavings.

An electrolysis cell only needs a couple volts to operate. Higher voltages don't help anything and make the cell much more dangerous. Working around high voltage/current power supplies and water with salts dissolved in it is an easy way to zap yourself. Make sure the power supply is current limited in some way, or is intrinsically low current (like a couple of C or D batteries), or at least protected with a fuse.

Based on the questions you (MisterSteve124) asked, you might want to do a bit more googling before you hurt yourself.

potatoflinger · Fri Aug 31, 2007 2:19 pm

beebs111 wrote:you do remember correctly, i enjoy igniting ballons of the mix, it is a prefect mix for detonation(not technically) and makes a fair sized boom

What do you mean igniting balloons? How would you fill a balloon with hydrogen?

Orpackrat · Fri Aug 31, 2007 3:42 pm

You can also use laundry soda.

MisterSteve124 · Fri Aug 31, 2007 7:03 pm

I'll be fine it would really be hard for me to hurt myself unless I light some in my face. This is basically the same setup I'm using:

Right now I'm just sealing up all the leaks in it then I'll give it a try.

beebs111 · Sun Sep 02, 2007 1:08 pm

i keep the electrodes close together and fill up balloons with the hydrogen/ oxygen mix and it explodes, pretty cool.

Blackett · Thu Sep 06, 2007 9:40 pm

yeah these are similar to cincinatti fire kites. courtesy of mr gurstelle.

except instead of slowly burning they explode. It's just some visco and a balloon.

You could have done this the easy way and busted out the reynolds and drain cleaner.

But if your gonna use it for metering and internal combustion and the like you did the right thing in terms of going with the pure stuff. Just be warned this stuff is scary in an enclosed space of any size.