during a lightning can the water react forming hydrogen and oxygen?

[CaptainPanic]

Is the majority of the earth's oxygen derived from plants taking in carbon dioxide and giving off oxygen or from lightning strikes on the oceans in which water is then broken into oxygen and hydrogen.

 

plants.

[Psimondo]

Glad I found this forum. I saw the most amazing thing today and have been searching the internet to see how it could have happened.

 

I live in Johannesburg and we have massive downpours with lightning. I was in an open car park and lightning struck a field on the other side of the car park. Very close. The astounding thing was that after the flash disappeared there was fire running up where the bolt had been. Absolutely, definitely fire. Orange and yellow rolling fire. In a line. It lasted about half a second and it was pouring with rain at the time. I couldn't believe what I was seeing but it lasted long enough, with a completely clear and nearby view that I am sure what I saw.

 

So my thought was that the lightning split the rain into hydrogen and oxygen (or some other flammable mixture) which then ignited. Any other theories?

[petrushka.googol]

I think this should be possible in seas and oceans (which are brine) and which assists electrolysis.

This should not ideally occur in fresh water bodies where the concentration of sodium chloride is appreciably lower. (just my idea...can't substantiate it though).

[Enthalpy]

Hot oxygen and hydrogen mix would have reacted faster than you can perceive.

 

Meanwhile (about October 2013, published in January 2014) one science team has by chance got a spectrum from ball lightning, which shows emission lines from soil elements: silicon, aluminium and their companions.

 

So my suggestion is that, as is now believed for ball lightning, the bolt vaporizes soil where it strikes, and you've observed the resulting plasma, which may take or not the shape of a ball.

[Peter BE cimp]

All in all, there are way too many variables to give a definite answer. For starters, to split a water molecule, you need a perfect circuit and around 241800 joules of electricity to split one dihydrogen monoxide molecule, but if the circuit is not perfect it could take up to 50% more energy. However, since oxygen is a diatomic molecule, (more or less meaning it needs 2 more electrons to become whole) it needs to have another oxygen atom with it, so if you were to split one water molecule, you would need to split 2, so you would need about 483600 joules of electricity or more, and that's still if you have a perfect circuit. Lightning has many factors to it, but normally a good bolt produces around 5 billion joules, witch again depends on many different factors. So if you could have a perfect scenario where the two water molecules were both in the center of a bolt of lightning, and that lightning had no other molecules to react with, and all of it's energy was focused on those water molecules, then yes you could split water into hydrogen and oxygen, though you'd be stuck with two H2 and an O2. But it must be unlikely since we don't seem to have too many Hydrogen or Oxygen explosions during storms.

Edited March 1, 2014 by Peter BE cimp

[John Cuthber]

Anyone who writes "For starters, to split a water molecule, you need a perfect circuit and around 241800 joules of electricity to split one dihydrogen monoxide molecule,"

clearly doesn't know what they are talking about.

That number is wrong by something like a million million million fold (maybe more, I lost track of the zeroes.).

[Sensei]

All in all, there are way too many variables to give a definite answer. For starters, to split a water molecule, you need a perfect circuit and around 241800 joules of electricity to split one dihydrogen monoxide molecule,

Incorrect.

237 kJ/mol of energy is needed per mole of water.

It's 6.022141*10^23 molecules of water, that has mass 18 grams.

For single molecule of water there is needed ~4*10^19 J or ~2.45 eV of energy.

2.45 eV is kinetic energy of single electron in 2.45 V potential difference.

 

In practice electrolysis can be performed using half that voltage ~1.23 V.

 

Anyone who writes "For starters, to split a water molecule, you need a perfect circuit and around 241800 joules of electricity to split one dihydrogen monoxide molecule,"

clearly doesn't know what they are talking about.

That number is wrong by something like a million million million fold (maybe more, I lost track of the zeroes.).

He didn't divide 241800 J by quantity of molecules.

237000 J / 6.022141e+23 = ~4e-19 J

4e-19 J / 1.602e-19 J = 2.45 Electronvolt energy.

 

It's discussed with more details on Electrolysis of water wikipedia page in thermodynamics section:

http://en.wikipedia.org/wiki/Electrolysis_of_water

Edited March 1, 2014 by Sensei

[Peter BE cimp]

Thank you Sensei, for starters I'm only in high school so it's not like everything I say is gonna be perfect, or anything in that case, and most of that stuff I put together through multiple wiki pages. But it still almost answered the original question. Here, https://www.youtube.com/watch?v=YuXKtkvTyrk, you put energy into water, you can split the molecules. My logic is that lightning could maybe split water, but it's highly unlikely.

[Aliakbar Kachwala]

I've got a bit more. I m thinking about creating these gas generation systems by electrolysis over the oceans and seas around us.

So can you pls help me out with it? Can greater amounts of gases be generated by the lightening occurences if all captured?

Pls help me out I m new to this blog.

[Elite Engineer]

He's wondering if when lightning strikes water, does the electricity split any of the water into hydrogen and oxygen molecules?

It sure does. How much...no idea.

[sethoflagos]

Doesn't lightning cause water to dissociate into hydrogen and oxygen not by so much by electrolysis but by thermolysis?

 

As I understand it, above 2000 C water starts splitting and by 3000 C over half of it is dissociated at equilibrium. So the 25,000+C core plasma temperature generated in the return stroke should easily be enough if only for a split second before it cools and the plasma recombines.

Edited August 14, 2016 by sethoflagos

[Sriman Dutta]

As there will be high P.D. between lightning strike and the ground, the water molecules starts to ionise. But, as lightning lasts for an extremely small period of time, I doubt whether any significant amount of oxygen and hydrogen will be produced or not.