Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Can we make water?

  1. Apr 26, 2009 #1
    can we make water??

    chemical formula of water is H2O
    hydrogen and oxygen are abundant in the atmosphere...so can we make water artificially by joining hydrogen and oxygen in the right quantity ?
     
  2. jcsd
  3. Apr 26, 2009 #2

    Borek

    User Avatar

    Staff: Mentor

    Re: can we make water??

    Almost no hydrogen in the atmosphere.

    Yes, we can make water reacting hydrogen with oxygen.
     
  4. Apr 26, 2009 #3

    HallsofIvy

    User Avatar
    Science Advisor

    Re: can we make water??

    I make water every morning.
     
  5. Apr 26, 2009 #4

    Borek

    User Avatar

    Staff: Mentor

    Re: can we make water??

    No, you make it all the time, you just pass it at the morning :wink:
     
  6. Apr 26, 2009 #5
    Re: can we make water??

    Then why we are we not using this technology in places were water is less?
     
  7. Apr 26, 2009 #6

    DaveC426913

    User Avatar
    Gold Member

    Re: can we make water??

    There is no free hydrogen on Earth. It is all already bound up in chemicals - mostly water. Hydrogen and oxygen react almost spontaneously to form water.
     
  8. Apr 26, 2009 #7
    Re: can we make water??

    Hydrogen and oxygen are very common elements to be found in rocks and minerals...so I think it would be at least technically possible to take a bunch of dry dirt and rocks in the desert and make water out of them. Of course, if this were easy to do, people would probably already be doing it.
     
  9. Apr 26, 2009 #8

    Borek

    User Avatar

    Staff: Mentor

    Re: can we make water??

    Technically it is possible, but it requires enormous amounts of energy and sophisticated technology. It will be cheaper to fly ice from Antarctic by blimps.
     
  10. Apr 26, 2009 #9
    Re: can we make water??

    It's even cheaper just waiting: in some tens of years global warming will deliver that ice to us gratis...:smile: :eek:
     
  11. Apr 26, 2009 #10
    Re: can we make water??

    Yeah you'll learn as you go on, just because you can do something doesn't mean it's practical enough to warrant doing it.
     
  12. Apr 27, 2009 #11

    chemisttree

    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

    Re: can we make water??

    http://www.army.com/blog/item/434" [Broken]

    We use hydrogen in the form of gasoline.

    C8H18 + 17O2 --------> 8CO2 + 9H2O
     
    Last edited by a moderator: May 4, 2017
  13. Apr 27, 2009 #12

    alxm

    User Avatar
    Science Advisor

    Re: can we make water??

    Actually there was an essay in Nature the other month about water shortages, and how it's not quite the problem its often made out to be. Countries with shortages of water compensate by importing food and using less water for agriculture.
     
  14. Apr 27, 2009 #13

    DaveC426913

    User Avatar
    Gold Member

    Re: can we make water??

    So, disease from tainted water is not one of the primary causes of death in 3rd-world countries???
     
  15. Apr 27, 2009 #14

    Borek

    User Avatar

    Staff: Mentor

    Re: can we make water??

    It is known fact that people in these countries are rich enough to import food. That is especially true in Somalia coastline villages, where money falls from the low flying planes.
     
  16. Apr 27, 2009 #15

    DaveC426913

    User Avatar
    Gold Member

    Re: can we make water??

    :tongue:

    Yes but that does not result in the conclusion that they do have fresh water to drink.
     
  17. Apr 27, 2009 #16

    russ_watters

    User Avatar

    Staff: Mentor

    Re: can we make water??

    Yes: "in rocks", meaning "not free".
    Exactly: since the oxygen and hydrogen isn't free, it requires a lot of energy to break it free from whatever chemical it is bound to, so it isn't easy.

    The atmosphere contains a very large amount of hydrogen and oxygen - but virtually all of the hydrogen is already bound to water. So the easiest way to create liquid water would be to simply condense it out of the air. Most affluent people in warm climates already do this, but they discard the water, dumping it on the street or down the drain. It is a waste product of air conditioning.
     
  18. Apr 27, 2009 #17

    alxm

    User Avatar
    Science Advisor

    Re: can we make water??

    It certainly is. The article was of course referring to more affluent, but water-poor places, such as the Arab nations.
    Which I kind of assumed was the context here as well, as providing water through 'chemical' means, be it desaliation or whatever, would generally be expensive and not an option for Somalia either.
     
  19. Apr 28, 2009 #18
    Re: can we make water??

    is this a cheaper way ? can we make large quantity of water using this technique?
     
    Last edited by a moderator: May 4, 2017
  20. Apr 28, 2009 #19

    Borek

    User Avatar

    Staff: Mentor

    Re: can we make water??

    Oh please, don't you see that to produce water here we are using octane - which is just an example of gasoline component? So in the effect you have to transport gasoline, burn it and reclaim water from the exhaust. It is not cheap.

    It can make sense when you already have to drive and burn gasoline, but it is not a way of making water.
     
  21. Apr 28, 2009 #20
    Re: can we make water??

    So we can't make water cheaply through chemical reactions..isn't it?
     
  22. Apr 28, 2009 #21

    Borek

    User Avatar

    Staff: Mentor

    Re: can we make water??

    Define "cheaply" taking into account resources available locally.

    You are looking for an easy answer "yes" or "no". It is not always possible to give such answer.

    Is 1 gram a lot?
     
  23. Apr 28, 2009 #22

    russ_watters

    User Avatar

    Staff: Mentor

    Re: can we make water??

    I'll go out on a limb and give an easy answer: no. Water is so abundant on earth, there is no point whatsoever in trying to manufacture it by chemical means.
     
  24. Apr 28, 2009 #23
    Re: can we make water??

    I'd go with that. What is more useful is a cheap, easy and scalable way to desalinate the water in oceans and purify waste water from various processes. There are many cheap and easy ways to desalinate water on small to medium scales and sewage treatment is pretty large scale nowadays.

    And remember, if you wanted to make water from other chemicals in regions that are frequently hit by drought you may as well transport water there. If you transported other chemicals, you would need to transport (sometimes significantly) more weight in order to produce an equivalent amount of water. You may as well just have transported more water in the first place :)
     
  25. Apr 28, 2009 #24

    chemisttree

    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

    Re: can we make water??

    You could think of that water as 'survival water' to be used only when normal channels of distribution are interrupted. It's the Army... they buy $600 hammers all the time.:tongue:
     
  26. Apr 28, 2009 #25
    Re: can we make water??

    It takes about 1000 pounds (125 gallons) of water to raise about 1 pound of grain (according to Lester Brown). It takes about 8 pounds of grain to get 1 pound of grain-fed beef. Modern diets consume more meat, so the water requirement per capita rises. The real problem is a combination of reduced water availability, reduced arable land (for a variety of reasons), a diet requiring more water to raise the food, and a rising population.
    Some countries with lots of oil, money and sand, like Abu Dhabi, have purchased a million acres of land in Sudan (near the Blue Nile) to raise their own food crops.
    Typically in most countries, 70 to 80% of water consumption is for agriculture.
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook




Loading...