# Electrolysis Questions

#### Billy S.

##### New Member
Hey, I'm new to electrolysis, and electricity in general. Although I have done a considerable amount of research, I still have a few questions, the reason being that I am hoping of developing a new engine concept, much like a Stirling Engine, that uses pressure produced by the electrolysis of water.

1. For anyone with chemistry knowledge, in terms of volume, how many liters (or whichever unit of measurement you prefer) of HHO gas will be produced from one liter of gas at SATP?

2. In a hypothetical situation, such as conducting electrolysis inside an enclosed pvc chamber, will that process require more electrical energy in order to conduct under those pressurized conditions?

3. How fast, exactly, can electrolysis be conducted at a high voltage of around 40,000 volts in liters per second?

#### Nigel Goodwin

##### Super Moderator
Sorry to disappoint you, but no serious site (such as this one) is likely to humour you by encouraging 'imaginary science'.

There are plenty of 'crazy' sites out there that do encourage such things, but you'll soon find out that none of them work.

#### Billy S.

##### New Member
Perhaps I should add to the list, "4. do you concur with my experiment?"

#### alec_t

##### Well-Known Member
Welcome to ETO, Billy.
I agree with Nigel. Experimenting in itself is fine, but you would soon prove to yourself that this HHO concept (which is by no means new) is a non-starter.
I suggest you do further research on electrolysis. Check out the voltage and current involved in industrial electrolysis.

#### jpanhalt

##### Well-Known Member
1. For anyone with chemistry knowledge, in terms of volume, how many liters (or whichever unit of measurement you prefer) of HHO gas will be produced from one liter of gas at SATP?
All of your questions are easily answered, at least in part, from a scientific standpoint. But, since you are into metascience, those answers won't apply.

I do wonder what the sentence quoted above means. If there is a typo, please correct it. Otherwise, explain what is HHO? Is it a triatomic molecule like water? How does it differ from water vapor? Most important, what "gas" do you intend to make it with?

John

#### Billy S.

##### New Member
I do wonder what the sentence quoted above means. If there is a typo, please correct it. Otherwise, explain what is HHO? Is it a triatomic molecule like water? How does it differ from water vapor? Most important, what "gas" do you intend to make it with?

John
HHO is a popular term used to describe the product of the electrolysis of water, and is not really considered a "scientific" term. My intention is to use the expansion of splitting H2O into H2 and O2 to push either side of a piston, then to ignite those gasses to provide the necessary force to displace the water contained in an enclosed receptacle, where the newly formed H2O molecules will replace the ones that were just displaced. I felt like designing something and this idea came up, then did some research and found out that this is analogous to a Stirling Engine, which pleases me in a way that I can compare it to something that actually works. Instead of used a heat source to create work in an enclosed system, I am instead using a battery to create work in an enclosed system. I have no idea whether this will actually work, but it is in my desire to try, because I'd rather see it with my eyes than to see it in text, and if you say I'm wasting my time then I will kindly disregard. Please inform me if my questions have no definite answers, because what I am doing is in no way scientific at this moment, and thank you all for your insight.

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#### Billy S.

##### New Member
All of your questions are easily answered, at least in part, from a scientific standpoint. But, since you are into metascience, those answers won't apply.

John
I am currently looking for as much information as possible, even searching through Google patents, and thanks for your insight as well.

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#### jpanhalt

##### Well-Known Member

In brief, a mole of gas at standard conditions occupies 22.4L. Thus, two moles of water vapor (44.8L; 1 mole = 18g) split into two moles of hydrogen and one mole of oxygen will occupy 67.2 L (i.e., 3x22.4). At constant temperature, you can work out the pressures from:

$P_{1}V_{1} = P_{2}V_{2}$

Note, many gases vary from the ideal gas law significantly.

John

#### Billy S.

##### New Member

In brief, a mole of gas at standard conditions occupies 22.4L. Thus, two moles of water vapor (44.8L; 1 mole = 18g) split into two moles of hydrogen and one mole of oxygen will occupy 67.2 L (i.e., 3x22.4). At constant temperature, you can work out the pressures from:

$P_{1}V_{1} = P_{2}V_{2}$

Note, many gases vary from the ideal gas law significantly.

John
You're right, and I decided to do some research on ideal gas. As a clarification, the water will be split as a liquid, instead of vapor, since vapor cannot idealy be mixed with electrolytes. That said, I doubt there will be a definite answer so I will have to rely on my own observations to determine the best possible solution.

#### jpanhalt

##### Well-Known Member
I agree that you should focus on electrolysis in the liquid phase, but you are incorrect in assuming that it cannot be done in a gas (https://books.google.com/books?id=Q...e&q=vapor phase electrolysis of water&f=false). Search on vapor phase electrolysis of water.

One mole of liquid water under standard conditions occupies a volume of 18 mL.

You still haven addressed any of the questions alec_t or I have asked.

Finally, how do you plan to generate 40,000 V at sufficient current to produce the amount of hydrogen and oxygen that you need?

John

#### Billy S.

##### New Member
I agree that you should focus on electrolysis in the liquid phase, but you are incorrect in assuming that it cannot be done in a gas (https://books.google.com/books?id=Q4RvmAri4jcC&pg=PA1365&lpg=PA1365&dq=vapor+phase+electrolysis+of+water&source=bl&ots=19VCn8e51R&sig=GoaHcqT9UZLmpO3ABzs6nYOdm2w&hl=en&sa=X&ei=W-aEVbmyKIqZNqPgvTg&ved=0CCsQ6AEwAg#v=onepage&q=vapor phase electrolysis of water&f=false). Search on vapor phase electrolysis of water.

Finally, how do you plan to generate 40,000 V at sufficient current to produce the amount of hydrogen and oxygen that you need?

John
Maybe I should consider that the water would function better in its gaseous state since there will be less friction altogether throughout the system, and it would eliminate the need for a condenser after the combustion stage, ultimately making the engine more efficient, not to mention many other benefits. As for the electrical input, I'm still working on it. I'm planning on using a pair of ignition coils connected to the four electrodes, where they will be supplied by a couple of car batteries.

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#### Billy S.

##### New Member
You still haven addressed any of the questions alec_t or I have asked.
Which might those be? I'm confused

#### jpanhalt

##### Well-Known Member
1. For anyone with chemistry knowledge, in terms of volume, how many liters (or whichever unit of measurement you prefer) of HHO gas will be produced from one liter of gas at SATP?
Both alec_t and I questioned what that sentence meant, particularly the underlined portion. What gas? If you mean water vapor, remember that at ambient temperature (e.g., 25°C), its vapor pressure is only about 20 torr (roughly 3kPa).

As for your voltage source/question, recall that with electrolysis the amount of product(s) produced depends on current. There are other ways to split water, but I am assuming you are not considering them here. The number of molecules in a mole of substance (e.g., water) is 6.02X10^23, which equals 18 grams of water. A coulomb is (C) is 6.24X10^18 charges. The oxidation of the oxygen atom in water requires transfer of 2 electrons. For one mole of water (18 g) that is approximately 12X10^23 electrons or roughly 2X10^5 coulombs, ignoring the Faraday constant (https://en.wikipedia.org/wiki/Faraday_constant). So, assume you want to convert one mole every 1000 seconds (17 minutes), you would still need on the order of 200 amperes of current (ignoring the Faraday constant). For confirmation, here is a discussion related to reduction of Zn+2 to metallic zinc that includes the Faraday constant (http://www.chem.purdue.edu/gchelp/howtosolveit/Electrochem/Electrolysis.htm). Your ignition coils will produce nowhere near that current.

John

#### Tony Stewart

##### Well-Known Member
Also keep in mind isolation of oxygen is paramount in H2 production. Even with N2 being the most dominant gas in air, 4% H2 with tiny ppm amounts of O2 is consider the Lower explosive Limit (LEL)

A litre full of H2 with a tiny amount of O2 as long as under the upper explosive limit UEL, can detonate a plastic pop bottle to be heard as far as the eye can see over the horizon, somewhat like a sonic boom.

#### jpanhalt

##### Well-Known Member
Unfortunately, I believe HHO is a stoichiometric mixture of hydrogen and oxygen. Why this discussion is allowed here, I don't know. Apparently, the current TOS do not restrict it. My next question to the TS was going to be: Please state in a single sentence what you plan to do. That is, if you succeed, what will the title or subtitle of your article in Science be?

I don't have any problem with helping a young person experiment with electrolysis or with Sterling engines. But, I think we need a realistic focus, or I see this thread wandering way off track

John

#### Billy S.

##### New Member
Both alec_t and I questioned what that sentence meant, particularly the underlined portion. What gas? If you mean water vapor, remember that at ambient temperature (e.g., 25°C), its vapor pressure is only about 20 torr (roughly 3kPa).

John
I have already explained what HHO is in an earlier post.
Unfortunately, I believe HHO is a stoichiometric mixture of hydrogen and oxygen. Why this discussion is allowed here, I don't know. Apparently, the current TOS do not restrict it. My next question to the TS was going to be: Please state in a single sentence what you plan to do. That is, if you succeed, what will the title or subtitle of your article in Science be?

I don't have any problem with helping a young person experiment with electrolysis or with Sterling engines. But, I think we need a realistic focus, or I see this thread wandering way off track

John
Briefly, my focus is to develop an apparatus that suffices the required current to lyse at a reasonable speed, in order to work at an rpm that will be useful. That is the very reason why I originally started this thread, since I have little experience in this area. My original plan was to use ignition coils, but at this point I'm not sure what I should do.

#### Billy S.

##### New Member
To keep this thread on track, I will say that if you wish to have more specific information as to how I plan on building the engine, ask in a PM and I will provide.

#### jpanhalt

##### Well-Known Member
in order to work at an rpm that will be useful.
Working at a "useful" rpm is not an answer. What we are talking about here is energy and work. Stirling engines work, but produce almost no usable power. There is an entire forum devoted to them. The last time I checked, a 5 HP Stirling engine was the size of a small house. There were lots of dreamers, but no doers.

So, in quantitative terms, what sort of power in watts do you intend to produce and what sort of power do you intend to use to produce those watts?

As for having this discussion via PM, if that is what you expect, you are in the wrong place. This is a public forum. There are no NDA's.

John