Making Water

Water is H₂O, that is two parts Hydrogen and one part Oxygen. So if we were to make water we'd need Hydrogen and Oxygen. The problem though is Hydrogen and Oxygen don't just exist by themselves in the real world, they exist as O₂ molecules and H₂ molecules which are fairly stable. In order to get the Hydrogen and Oxygen we'd need to use energy to break up the O₂ and H₂. Then once they are broken up, we'd have to make sure they didn't just recombine again, or form other compounds with materials nearby. This requires a pristine environment and would be very expensive.

So to answer your question, you could make water out of Hydrogen and Oxygen, but it would be very expensive and inefficient.

I have heard that H2O in its pure state is deadly for human consumption. Any truth to this?

Only if you breathe it in liquid form.

Great Answer.

Dihydrogen monoxide is a major component of acid rain, has been found in the tumors of cancer patients, and causes a large number of accidental deaths through inhalation.

Join the Effort to ban dihydrogen monoxide!

Or if you breath it in super-heated vapor form (live steam).

Of if a water hose is connected to your mouth (or the other end of your digestive tract) and it is pumped in at high pressure, causing internal organs to swell and explode.

A perfect way to find out if this works, is to use a test subject. Just watch out for the med in blue with the cars with flashing lighs when you test this theory out.

Isn't this is why the USA invented "Extraordinary Rendition". So that the guys in blue and those who respect the "Constitution" and "Bill of Rights" wouldn't be unduly concerned?

its true. apart from needing the minerals in water, osmosis occurs in our body, so our cells would become so full of water that they'd burst. not very good for our body, right?!

The reason is that molecular H2 does not exist in large amounts anywhere on earth. H2 is too light to be held by Earth's gravity, and leaks away into space. In order to make water you would have to seperate Hydrogen from some other compound, such as Methane. This would require huge amounts of energy, as well as a good supply of natural gas or some other source. It's much cheaper to distill saltwater.

And no, pure H2O is not toxic. I think the source of this rumor is that your body does need certain trace minerals that would not be present in absolutely pure water, so in theory if you only drank absolutely pure water for a very long time you might get sick.

I drank distilled water for years with no adverse effects. I have heard stories that it would "leach minerals from you bones" but I think your body is smarter than that. If your nutrition is good otherwise I don't think a lack of minerals in your water has any effect. Of course if you diet is very poor, no amount of mineral content in water is going to make up for that either.

I question the basic premise - that pure water is good for us. Humans have been around for eons, and only in the last couple hundred years have we been able to make pure water. We are biologically set up to take water as it comes to us, and only in certain cases does water contain problem chemicals. Our modern mania for cleanliness is only weakening our immune systems.

Any pure H20 that you drink isn't going to remain pure very long in the gastro intestinal tract. By the way if we have evolved so well why can't we drink salt water since there is about 50 times as much salt water as there is fresh water, ocean going fish can drink salt water so why cant we?

A few years ago in my high school bio class, the concept of pure water being harmful came up. I didn't really buy it, but I thought about it for a while. The only way I could think of that pure water would be harmful is if you were to sit in a constantly replenishing tub of the stuff. Diffusion would cause the ions and other solubles in your skin to "leach" out into the bath, and water to enter your body. By continuosly re-purifying the water, the soluble gradient would always be maintained. I could never figure out what you would die from though... vitamin loss, or the massive water content of your cells causing you to explode...

Fish don't drink. They live on the osmosis principle. As to that evolution thought, how far from the ocean are you? I personaly live 3 or 4 hours from the Atlantic by car, speeding. So I would guess that as a general rule most of the world doesn't live within a sensible water carrying distance either. There was more fresh water spread out where there were more people. Just think how far are you willing to walk for water every day?

Osmosis will move water from one solution to another solution through a semi permeable membrane from the less concentrated solution to the more concentrated solution. This means that fish living in fresh water can absorb water via osmosis but salt water fish can't. Salt water fish use their gills to remove the salt from the water before they consume it. See "Do fish drink at http://www.answerbag.com/q_view.php/11721 " . To the other part of the question I live less than 1 Km from the sea and since something like 90% of the people in Australia live within 20 Km of the see it would be great if we could drink salt water. The other problem in Australia is that a good proportion of the subteranian water is also too salty to drink.

Have you carried five gallons of water 1 Km? It ain't easy. I am thinking on the evolutionary period not todays mass transit. I don't disagree with the idea I just think that it is unlikely for evolution to branch in such a way.

distilled water in bottles is not 100% pure. The reason for this is because the .1% of contaminated water is not really contaminated, it just has trace amounts of minerals that give it a little bit of a taste. So it isnt possible for distilled water to "leach minerals from your bones".

Wow! I've read some wierd comments before, but this one has brought out some of the wierdest!

"Humans have been around for eons, and only in the last couple hundred years have we been able to make pure water." Huh? Pure water was available from RAIN several thousand years ago -- before pollution changed some of it into ACID RAIN. Now, it's only available most places on earth.

"Fish don't drink. They live on the osmosis principle." This statement leads me to believe that the person who wrote it has never eaten anything under water. It also makes me wonder if he knows how the human body absorbs nutrients from the stuff we eat and drink.

" . . . you could make water out of Hydrogen and Oxygen, but it would be very expensive and inefficient." This one is a little bit true: Hydrogen/oxygen PEMFC (proton exchange membrane fuel cells) produce water from H2 and O2. Fuel cells are inefficient in producing water, and they aren't cheap yet, but they produce another usuable thing: Electricity. Fuel cells also use something akin to osmosis.

And the best one: "There was more fresh water spread out where there were more people." People gathered around fresh water sources. Water did not "spread out where there were more people!"

I love these kind of posts. I have some responses to you observations:

Regarding the pure water comment, actually rain is not entirely pure. Rain water picks up particles and ions with just exposure to air. In order to make pure deionized water special filters are required.

You wrote "This statement leads me to believe that the person who wrote it has never eaten anything under water."--I have no idea what you are talking about here.

The original post was the question "If we know the chemical formula for water, why can't we just make it" and I answered "You could make it but it would be expensive and inefficient" Wow, what a weird answer.

As for the statement "There was more fresh water spread out where there were more people.", I'll admit this could have been written better, but I think most people would understand that he's saying that Humans tend to live around fresh water, not salt water. I'm pretty sure you're the only one who thought he meant that fresh water follows people around.

Now I'll grant you that evolution thread was a little weird but not to the extent you made it out to be.

Couple of things regarding this subject. Pure water can be made simply by igniting hydrogen gas in the presence of oxygen. I do not understand this whole H2 to H and O2 to O thing, that would not be necessary and would require massive amounts of energy (think plasma). The expense out weighs the benefits, as humans do not need absolutely pure water. We can use reverse osmosis, vacuum evaporation, and deionization to purify water well past the extent we need. We currently can desalinate water quite effectively and cost efficiently, frequently it is our Environmental Quality /Protection Laws biological opinions/reviews and public agendas that disrupt the process of installing Desal facilities to produce high quality water from sea water (remember the stuff you remove from water has to go somewhere). Even if you were to make water from hydrogen and oxygen, the source of the hydrogen and oxygen is water (this take substantial amounts of energy, and leaves residue to be disposed of). What do you do with the residues from the process? (If your answer is dump the salt back in the Sea, you would never get through the CEQA/NEPA processes with out substantial cost and mitigation). Trying to make water pure must adversely affect something somewhere in the environment to some degree. Desalination is a common practice more so in areas of the world where the value of potable water out weighs the environmental impacts and energy cost. As water gets more expensive and our desalination technology gets more efficient, you start to see more first world nations starting the process of permitting/desinging/installing along the coast, and transferring water rights for larger inlands source towards more inland communities. Also, over all there is not a shortage of water world-wide, the perception of a shortage due to large population centers located in areas where there are local shortfalls (Think La/San Diego=Desert=insufficient naturally occuring fresh water). People want to live in dry rain-free areas near the sea because of the nice climates/weather, which means not much natural fresh water, and/or conserve freshwater resources for drier periods poorly. Finally, If you were thinking that transport of hydrogen and oxygen would be a better water to deliver pure water, from the Sea to thouse areas where it is needed, the volume required to transpot these two gases would be magnitudes larger than the volume of water that would be formed.

Hydrogen gas is H₂ and Oxygen gas is O₂ by definition, please look it up, they are called diatomic molecules. See link:

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

One of the most interesting proposals to date has been to tow large icebergs to parched areas and beach them. Surround them on the ocean side with sand and then collect the melt. There are numerous technological bridges to be crossed before this becomes completely practical, but a medium sized berg would supply a lot of water for a while.

I enjoy posts like these also. Sometimes I just can't help myself and respond when maybe I shouldn't. My mother even taught me to not say anything if I didn't have anything nice to say, but I'm getting old and forgetful.

Roger, I wasn't picking on you. I know about rain picking up particles and ions, etc., but the point was that rain is not far from pure water; certainly drinkable (non-poisonous) water in most cases. I am familiar with the process to deionize water -- I've installed several filtering systems to do just that, including some which use an osmostic process.

The statement: "You wrote 'This statement leads me to believe that the person who wrote it has never eaten anything under water.'--I have no idea what you are talking about here." is part of a larger statement in a paragraph by itself: "'Fish don't drink. They live on the osmosis principle.' This statement leads me to believe that the person who wrote it has never eaten anything under water. It also makes me wonder if he knows how the human body absorbs nutrients from the stuff we eat and drink."

I also didn't know I commented on evolution, but that's another story.

You should definitely respond, I'll take the person who puts themself out there and risks being wrong over the person who doesn't every time.

I thought your comments were taking a lot of stuff out of context to make it look dumb. Like the fresh water comment and the pure water comment. That's unnecessary, all you have to do is wait and we'll say something dumb on our own in the correct context. Just take a look at my "facts" on quasars in another post, half of which turn out to be wrong;)

I still don't understand the eating under water thing.

Thank you for the answer. And thank you for the interesting path this thread wove.

Hello all

I am very curious to this subject.

Lets say if we consider that cost is not applicable.. Lets say humanity is the cost.

What technology exists to combine Hydrogen and Oxygen to make water?

This is an explosive combination as I understand. Is there any information on yields or other catalysts such as lasers that could control this chemical equation? If the hydrogen fuel cell can produce energy for a car to run and provide water as the bi-product can this technology be refined to focus on high yields of water vs energy production?

"Making water"?

"Pure water"?

Water with less than 60ppm of calcium in it tastes 'king awful, that's why. If water isn't available from natural sources, then making it by any technique will do, provided that part of it that is consumed is re-hardened before being drunk.

Pure water doesn't stay pure very long. Any hint of biology will tend to multiply exponentially until the food source in it runs out.

Water suitable for drinking is made on ships and oil platforms using two basic processes, depending on the availability of either waste heat or of electricity. If copious waste heat is available, then evaporating and condensing the vapours of sea water will do; if electricity is available then reverse osmosis [RO], possibly with a pressure exchanger to economise on energy, is an alternative.

• Cyprus uses RO on a municipal scale to create drinking water from Mediterranean seawater.
• London has just established a municipal-scale RO works at Beckton as a long-term insurance policy against the predicted effects of population and climate change.

The chosen technology to make drinking water depends on economics. In the UK, potable water is delivered continuously and on demand from boreholes and rivers via municipal works at about £0.60GBP per tonne delivered; a tonne of RO water will nead about 4kWh to make and a bit more to deliver, at a buy-in price of around £0.11-0.13GBP per kWh. The mathematics are relatively simple: while boreholes and river sources are relatively plentiful it makes economic sense to use these than less economically favourable techniques that require the amortisation of substantial levels of investment.

The solution on board the International Space Station, for instance, would be completely different, and the economics of it are secondary to the consideration of take-off weights.

What was the question again?