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Separate Hydrogen and Oxygen from Water Through Electrolysis

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Electrolysis a method of separating elements by pushing an electric current through a compound. It is used in various industrial applications such as removing copper from its ore. It is also used to separate hydrogen and oxygen from water. Electrolysis isn't the most efficient way to obtain hydrogen, but it is one of the easiest and cheapest ways to "homebrew" hydrogen.

Hydrogen is the most abundant element in the universe. With the "green-energy" craze and talk of powering our future oil-free economy on hydrogen, it has gotten much attention in the last few years. Learning about this potential fuel of the future is important and interesting. Besides, hydrogen is a powerful fuel, and blowing stuff up in the name of science is fun .

 
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Step 1: Electrolysis of Water - An Explanation

This section is an explanation of the electrolysis of water, feel free to skip it if you don't find it interesting.

2H2O(l) = 2H2(g) + O2(g)

As everyone knows a water molecule is formed by two elements: two positive Hydrogen ions and one negative Oxygen ion. The water molecule is held together by the electromagnetic attraction between these ions. When electricity is introduced to water through two electrodes, a cathode (negative) and an anode (positive), these ions are attracted to the opposite charged electrode. Therefore the positively charged hydrogen ions will collect on the cathode and the negatively charged oxygen will collect on the anode.

When these ions come into contact with their respective electrodes they either gain or lose electrons depending on there ionic charge. (In this case the hydrogen gains electrons and the oxygen loses them) In doing so these ions balance their charges, and become real, electrically balanced, bona fide atoms (or in the case of the hydrogen, a molecule).

The reason this system isn't very efficient is because some of the electrical energy is converted into heat during the process. There have been reports of 50%-70% efficiency, but I doubt that is possible in a home environment. Anyway, enough with the boring stuff, lets go make some gas!
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BigVerninOz3 years ago
Hi All, probably a bit late to add to this but my grandfather was a cameraman for a big TV enterprise in the 70's. He has footage that he kept from a story he filmed of a man mowing a lawn with a mower with a tank full of water. This man starts by putting a cup full of fuel in the mower and mows a strip of lawn after which he tips the whole thing upside down emptying the splash of fuel. he then puts the tank under a tap and fills it then proceeds to mow for 45mins. The carby on the side was bizzare looking but not much bigger than standard and the footage is clear and the man shows that there is no other hoses or tanks or anything that would conceal fuel on the mower. 2 weeks later they went to do a follow up only to be told that he could no longer discuss his device as the design had been purchased by British Petroleum and was no longer his. This was early 70's black and white film, no special effects or trick photography just continuous unedited filming. My pop was no saint but was a war vet with nothing to prove or gain from this. He also told me about Nicola Tesla who was making ozone in the 1800's as well as energy transmission etc. My pop wanted me to have an open mind and to not ever fall into the 'Ignorance is bliss' world everyone else lives in. He also used to say that people believed the earth was flat but we now we know better. Believe what you want, in time we will all know better.

http://www.unige.ch/sciences/crystal/yvonk/offprints/IJHE-lawnmower-proofs.pdf

I actually saw that clip on TV when I was a kid living in Sydney, bloody hell eh, small world. Gob smacked me then and still amazed that such things are still so far under the radar. Tragic bloody tragic. All I can say is for all those taking a punt and having a go good on you and keep at it.

Further to my original post it turns out he wasn't the cameraman for the filming but instead was the sound operator. He was normally the cameraman but filled in for sick sound guy on his day off. I have got a name for the cameraman on the day as he has the original footage and had made a copy for grandpa. Glad to know someone else seen it, hoping to get or make a copy of footage again to show others. Thanks for posting a reply.
KaranA119 days ago

how can I convert the hydrogen gas to store it in a battery?

ssingh15821 days ago
Please provide information about voltage to be supply and qty of water
Justfyi1 month ago
The diagram needs to be corrected. Cathode is the negative side that attracts positively charged ions and the anode is the positive side that attracts negatively charged ions. That being said your polarity needs to be switched on your diagram as the cathode is connected to the positive terminal and you have positively charged hydrogen atoms collecting on it while the anode side is connected to the negative side with negatively charged oxygen atoms collecting on it, which isn't correct. Once the split gases receive or lose their respective electrons they become neutral (stable) and stay as their component parts only to combine again when burned or become part of another chemical process.
Justfyi1 month ago
Your diagram is incorrect. Change the polarity of the input voltage and correct the symbols inside the water for the anode and cathode (unless that plus sign in there represent the hydrogen charge and the negative for the oxygen,neither way it's going to confuse people and needs to be corrected)
srimal18 months ago
Why is volume of gas collected in the testtube over anode less than that collected over the cathode during electrolysis of water? Can i get this ans as soon as possible

Water "H2o" is 2 parts Hydrogen one part Oxygen...So you'd get more hydrogen, then oxygen gas.

jayjoy747 srimal18 months ago

water molecule is formed by two elements: two positive Hydrogen ions and one negative Oxygen ion. The water molecule is held together by the electromagnetic attraction between these ions. When electricity is introduced to water through two electrodes, a cathode (negative) and an anode (positive), these ions are attracted to the opposite charged electrode. Therefore the positively charged hydrogen ions will collect on the cathode and the negatively charged oxygen will collect on the anode

krisha5 years ago
why do you need to put salt to the water?
robhick krisha5 years ago
don't laugh ,add urine . works great.. salt is a no no no no

If you're worried about corrosion, use baking soda. Less discusting haha

pmonkeey krisha5 months ago

To increase the conductivity of the water (more electric flowing Amps)

But try Baking soda not salt monitor the poisons carefully

Keep clean water ready to dilute any spills and so on.

pmonkeey5 months ago

Your diagram is wrong you have the positive from the battery going to a - negative sign?

Dantex7 years ago
Hydrogen is negative and oxygen positive.
Thank you dantex!I was beginning to have a bit of confusion because the diagram appears to be backwards in respect to the anode and diode

Hydrogen bubbles are tiny it's the smallest atom

Oxygen Bubbles are larger if you don't see Oxygen switch to a pencil lead (Graphite) instead of wires into the fluid.as copper wires will give you a green muss at the bottom of your container as the oxygen leaves with some copper on board for the ride :)

IMG00477-20140625-0109.jpg
hooloovoo33 (author)  Dantex7 years ago
Do you mean their respective charges, or that oxygen comes off the neg. and hydrogen off the pos. ??
When you connect battery in electrolysis you get hydrogen on negative and oxygen on positive.
jayjoy7478 months ago

extract from the site gives you the answer........

water molecule is formed by two elements: two positive Hydrogen ions and one negative Oxygen ion. The water molecule is held together by the electromagnetic attraction between these ions. When electricity is introduced to water through two electrodes, a cathode (negative) and an anode (positive), these ions are attracted to the opposite charged electrode. Therefore the positively charged hydrogen ions will collect on the cathode and the negatively charged oxygen will collect on the anode

Weregoat1 year ago
I have a question -

While this is a neat way to obtain hydrogen, what of the oxygen?
I guess without going too far in-depth, can we get breathable oxygen from water? Or is the Oxygen gas chemically different from the O2 we know and love (to breathe)?

I'm not very chemistry minded, and it's been years since I've even taken a course on science, but I'm wondering if it is possible to get breathable air from water.
well, don't worry for not knowing. what you should know is that the oxygen molecules will collect near one lead of wire, the hydrogen will collect on the other. this is because water molecules are polarised, and one side is more positive than the other. this means that if you place a collector of some sort (like the test tube) on both leads, then one will fill with hydrogen, the other with oxygen. if you do this, be sure to not use something that reacts with oxygen as your electrolyte, or else the resulting gas could be toxic. but, as long as the electrolyte can't react with the oxygen, the atoms should conect into O2, or breathable oxygen.
The only issue being that pure O2 is toxic to your lungs and will corrode them. The optimum level of O2 in the air is around 17%. If you really want breathable air, just use a compressor. Pure O2 is used to knock people out in hospitals, or liquid fueled rockets. Breathing it directly would get you high after a little, and destroy your lungs after extended use.
ttrhntye mlinguist10 months ago
It's not used to "knock people out" in hospitals.
Breathing it at normal pressures doesn't get you high.
The low humidity in Aviation Breathing Oxygen (100%O2) does make your mouth a bit dry, but it doesn't destroy your lungs.

Pure O2 doesn't "corrode" your lungs. Toxicity depends on pressure. When diving, at some pressure greater than one atmosphere, it's toxic yes.  So is air at more-elevated pressures because of the elevated partial pressures of the oxygen and nitrogen in the air. Aviators routinely use 100% O2 at pressures between 1.0 and about 0.4 atmospheres. In fact, if your cabin altitude is above about 30,000 feet you'd better be breathing 100% O2.
bretac10 months ago
I made a hydrogen maker for my van . I used a half gallon glass jar filled with distilled water mixed with baking soda . I connected my positive wire to stainless steel drain plugs and just submerged the negative wire . I was wondering wondering what type of material is best used for the anodes and cathodes ? Plus will any water work as good as distilled water ? 3rd how much hydrogen would I have to produce to be able to run a 4.3 V6 on hydrogen alone ? As far as converting my gas tank to a hydrogen producing container would the process cause any damage to the materials that the tank is made of ? .
onebadvette4 years ago
One thing people need to keep in mind with this kind of setup is that you are not going to get the kind of flow required to do any kind of work that will help MPG. These HHO system type things are sold on ebay with plans etc. The amount of work and energy required to get a substantial amount of gas is...substantial. I don't have a degree in physics, but used to run a machine that was designed to make pure O2 for submarines. It required 1050 amps of DC current to produce 120scfh with double that for Hydrogen which we disposed of overboard. The amount of gas produced from a 12 volt source is not enough to help your car. It's a cool science experiment for school, but that's about it. Former MM2(SS) A-gang type. (google what that is. I also used to run the CO2 scrubbers and COH2 burners for atmosphere control.)
1050 amps = about 7 solar panels on a sunny day
Not true. You can't even flow 1050 amps down a regular home wiring because it only handles 20 amps.
Go study some more would ya
are you familiar with the inverse relationship between voltage and amperage? I can have a power source that is only a few volts that is 100 amps; or something could put out only a few amps that is 120 volt. Solar panels put out DC current which is typically converted to AC power and manipulated to usable 120volt/15 amp circuits. Your remark "Go study some more would ya" is meant to be inflammatory, and I don't appreciate it...
AMPS x VOLTS = Watts

100 amps x 10 volts = 1000 watts
10 amp x 100 volts = 1000 watts

Nothing you can do will change the relationship between amps and volts

Amps is NOT power
Volts is NOT power

In order to get power - you need both and they both are related.
I aint tryin to do nothin, except maybe explain to you how amps and volts are inversely related (as you seem to demonstrate so well in your post above). you are the one who saw my post of 7 solar panels generating up to 1050 amps and became rude. You may want to add one (or 2) more lines to your example above for a group of 7 solar panels collectively generating 1050 amps:
"100 amps x 10 volts = 1000 watts
10 amp x 100 volts = 1000 watts"
1050 amp x 1 volts = 1050 watts Hmmmm... OR
1 amp x 1050 volts = 1050 watts
-now, go to your menards store and buy yourself an electricity book...
PS-the relationship between amps and volts is tweeked everyday in our world it is nothing new; If you think your public utility powerplant is producing 20 amps of 120 volt current to your house, so that it don't trip your 20amp breaker, then I aint got nothin more for ya; 'cept you might wanna go to your menards store and see what kinda books they got on the shelf there for ya.
I do understand that the utility company supplies lots of amps to your home - I also understand that a typical home IS FUSED at 100 or 200 amps. After those fuses, there are branches of 20 amp fuses.
A typical home requires 10KVA for peak and an RMS value somewhat lower in the 4KVA arena.
Your 1050 amps is crazy - Even if you had that, you would require a copper conductor with diameters in the range of 5 inches diameter.
YOU WILL NEVER GENERATE 1050 AMPS from your solar toys.

I design computerized weld controllers which control up to 25,000 amps at 10 - 5 volts. The conductors are very short and very large diameters. I also design Rogowski coils (you'll have to Google that since the detail is not available at Menards) to measure the high currents.

So, I hope you can realize that after 35 years in the electrical design arena, I know just a little bit about electricity.

Now, if you ever get off your high horse, I can even tell you how to design a solar system that actually works..
Hmmm, looking back on this; I am thinking I must have meant to say 1050 watts instead of amps. It makes more sense that way. Guess I better get on down to Menards and see if I can't find me an electricity book...lol
PS-how many amps you get out of 7 solar panels would depend on whether you lined them up in series or parallel. Just like flashlight batteries (also dc power), if they are all connected together like a train (in series) the voltage increases with each battery but the amps stay the same. If each battery is routed to the load separately (parallel) the voltage stays the same but the amps go up. Solar cells are a dc power source, they behave alot like batteries; and people who don't respect them get killed very easily because the amps do accumulate to dangerous levels. Didn't grace your post with a response sooner cause you teeed me off...
OK then - Go ahead and flow 1050 amps down your house wiring. Should work fine with those 20 amp breakers. Maybe you can find 1050 amp breakers at Menards?

Amps drawn from a source are purely dependent on the load - For instance, if you connect nothing to batteries - regardless of how they are connected, nothing flows.

More current will flow from series devices assuming the same load, and in fact a double voltage creates a quadruple power since both the current and voltage are doubled. Amps x volts = watts.
"OK then - Go ahead and flow 1050 amps down your house wiring. Should work fine with those 20 amp breakers. Maybe you can find 1050 amp breakers at Menards?"
-I already explained this below; but solar panels are not wired directly to circuit breakers. The power has to be converted from DC to useable 15amp 115volt circuits before going to the breaker box. You do not seem to be well informed enough, to be so critical... Who's goin to menards now?

"Amps drawn from a source are purely dependent on the load - For instance, if you connect nothing to batteries - regardless of how they are connected, nothing flows."
-interesting that you choose to use a battery as your analogy. I challenge you to get more than 2 amps out of a short circuited, single, C cell, battery. Likewise a solar panel will only put out what it will put out, I don't care what you or the "load" want to take from it. Your logic/theory about amps drawn being "purely dependent on the load" is probably taught in tech schools across the land for people working off the grid which is a seemingly/relatively limitless source of power. -Who's goin to menards now??

"More current will flow from series devices assuming the same load, and in fact a double voltage creates a quadruple power since both the current and voltage are doubled. Amps x volts = watts."
-OK now you introduce another word into the discussion; "current" without clearly defining it. Current is the flow of electrons typically among electricians referred to in volts, but more scientifically referred to in amps. It can be ACurrent or DCurrent. Anywhoo; you aint gettin 4x the current(energy) out of a battery unless you are usin 4x the batteries. 4, 1.5vdc batteries in series will give you 4x the volts or 6 volts.
4 batteries in series=4x the volts
4batterries in parallel=4x the amps
which of course equals alan goin to menards to get whatever kind of batteries he is talkin about ...
tmind alanwms2 years ago
LOL,

A home is 60-100 amp, a branch circuit off the main is 15-30 amps.

I cannot say study more because youd need an electrical license but your point is vaild, it most likely makes .01 microamps.
I have to disagree with you. I have worked with HHO for 7 years. Our engines receive 14.7 parts of air to each part of fuel vapor. The oxygen content of that is is 20% or less. That is not enough oxygen to burn all of the hydrocarbons. The result is carbon monoxide and a few other greenhouse gases. Adding more oxygen content --- to the metered air --- will increase the burn so that more of the metered fuel is burned and less metered fuel makes it out the exhaust. Oxygen is an oxidizer, without it, the chemical process of combustion will not produce a flame. The more oxidizer, the hotter the flame. People that are using HHO in their vehicles have near zero greenhouse emissions. The engines run smoother, have more power, oil changes are fewer, fuel economy follows -- if and only if the government mandated vehicle computers allow it. They are programmed to maintain 14.7 parts of air for each part of fuel vapor. There lies the problem with fuel economy. The added oxygen, from HHO, does make a positive difference. The added Hydrogen is only a small amount of fuel, but it too makes a difference.
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