Why can oxygen be collected by water displacement?
102988
Since Oxygen is a gas, it is less dense than water...hense it will float.\n\nIf you produced Oxygen underwater, as it is produced, it will buble up.  If you place some type of container (filled with water) above the bubbles, the Oxygen will collect there and displace (push out) the water.\n\nThis picture should give you the idea,\nhttp://intro.chem.okstate.edu/1314F00/Lecture/Chapter5/Gasoverwater1.GIF
194414
Water is denser than air and transfers heat more rapidly.
51965
Hmm...  If I remember the physics right, it goes like this: Take two parts hydrogen and one part oxygen and mix them in a chamber with a catalyst and a proton exchange membrane and you get water and electricity.
1044303
the only way I can see this, is to disolve ozone (O3) into water. Ozone is already used to disenfect chirgical tools
61416
Yes you could. Free hydrogen (H2) is rare in the atmosphere though, so you would have to buy industrially obtained hydrogen (which mostly comes from natural gas) which is expensive so its always cheaper to drill a water well or something. But yes, if you want to combine oxygen and hydrogen, and light it with a match, you will get water. Good luck trying to contain it after it goes from gas to the combustion product of hydrogen and oxygen, which will be water vapor (steam).
972563
I'm beginning to be convinced....Seems like nature loves recycling...Oxygen, water, why not us?
561732
water displacement and boyles law of bouyancy
732892
It is grabbed from the CO2 in the air.  Protosynthesis involves combining carbon dioxyde from the air with water to produce sugars and release oxygen.
646959
2H2 + O2 ---- 2 H2O\n\nYou can easily obtain water around the house.
346480
They have breathing holes on their heads.When they need oxygen,they will swim onto the surface of the water and take in the oxygen.
882542
Breathing, the process whereby an organism (living thing) obtains oxygen from its surroundings, to take part in internal chemical reactions which break down food to release energy. Breathing also usually gives out waste carbon dioxide as an unwanted by-product of these reactions. Breathing is one aspect of respiration, which is a term that includes both physically obtaining oxygen, and also using it in chemical pathways inside cells to release energy—the process of cellular respiration\n\nMany aquatic animals obtain oxygen dissolved in the water by muscle-powered movements, such as when the forward motion of a fish or the pumping actions of its mouth and throat force a flow of water over its gills ( See also Fish). This is underwater breathing. Tiny organisms “breathe” by the process of passive seepage or diffusion of oxygen through their body surfaces. Plants also obtain oxygen by diffusion from the air or water around them, usually into the leaves.
166600
The idea is to add the acid to the water and then pass a current through the water.  The water will split into Hydrogen and Oxygen.  The bubbles of these gasses can collected in tubes, the H will produce twice as much gas as the O.\n\nThe rocket can be powered by igniting the hydrogen.\n\nI think the citric acid is more reactive than absorbic acid, but any thing will do including vinegar (acetic acid).
261005
Apparently groups in Sweden, Australia, and the UK are working on this. There are probably others as well. They are making progress. It does appear that this might allow the industrial scale separation of water into hydrogen and oxygen, and the reduction of atmospheric CO2. \n\n\nRecently, Jim Barber and So Iwata of Imperial College in London identified the actual crucial molecules that are used to split water by plants. This might lead to huge advances eventually. It is quite exciting.
868418
# Anoxic autotrophs: Obtain hydrogen from chemicals such as sulfur.\n[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[Dead Zones are areas where the bottom water (the water at the sea floor) is anoxic, meaning that it has very low (or completely zero) concentrations of dissolved oxygen.]]]]]]]]]]]]]]]]]]]]]]]]]\nDead Zones are areas where the bottom water (the water at the sea floor) is anoxic, meaning that it has very low (or completely zero) concentrations of dissolved oxygen. These dead zones are occurring in many areas along the coasts of major continents, and they are spreading over larger areas of the sea floor. Because very few organisms can tolerate the lack of oxygen in these areas, they can destroy the habitat in which numerous organisms make their home.\n\nThe cause of anoxic bottom waters is fairly simple: the organic matter produced by phytoplankton at the surface of the ocean (in the euphotic zone) sinks to the bottom (the benthic zone) where it is subject to breakdown by the action of bacteria, a process known as bacterial respiration. The problem is, while phytoplankton use carbon dioxide and produce oxygen during photosynthesis, bacteria use oxygen and give off carbon dioxide during respiration. The oxygen used by bacteria is the oxygen dissolved in the water, and that’s the same oxygen that all of the other oxygen-respiring animals on the bottom (crabs, clams, shrimp, and a host of mud-loving creatures) and swimming in the water (zooplankton, fish) require for life to continue.\n\nThe "creeping dead zones" are areas in the ocean where it appears that phytoplankton productivity has been enhanced, or natural water flow has been restricted, leading to increasing bottom water anoxia. If phytoplankton productivity is enhanced, more organic matter is produced, more organic matter sinks to the bottom and is respired by bacteria, and thus more oxygen is consumed. If water flow is restricted, the natural refreshing flow of "oxic" waters (water with normal dissolved oxygen concentrations) is reduced, so that the remaining oxygen is depleted faster.\n\nMany of the areas where increasing bottom water anoxia has recently been observed are near the mouths of major river systems. While Satellite images can’t see the bottom of the ocean, they can see the surface, where sediments from rivers mix with ocean waters. The images shown here are Satellite images (SeaWiFS) observations of the Mississippi River delta, the Yangtze River mouth in China (The Yangtze River mouth is not currently identified as an area with an associated dead zone, but such conditions could develop there in the future), and the Pearl River mouth in China, near Hong Kong.\n\nSeaWiFS can also observe areas where water flow is restricted, such as the Baltic Sea in Europe. The image on the left features Denmark after strong storms caused flooding and increased sediment suspension in the Baltic. On the right is an overview of the Baltic Sea, including a plankton bloom in the Skagerrak just north of Denmark.\n\nThe apparent cause of the creeping dead zones is agriculture, specifically fertilizer. While fertilizer is necessary to foster bumper agricultural crops, it also runs off the fields into the streams and rivers of a watershed. When the fertilizer reaches the ocean, it just becomes more nutrients for the phytoplankton, so they do what they do best: they grow and multiply. Which leads to more organic matter reaching the bottom, more bacterial respiration, and more anoxic bottom water.\n\nThese effects can be magnified by catastrophe. When the heavy rains of Hurricane Floyd caused extensive flooding in North Carolina in September 1999, the heavy load of nutrients (from dead animals, flooded animal waste ponds, and numerous other sources) reached the sounds that lie between the coast and the Outer Banks, oxygen levels in the water plummeted. The picture at the top of the page shows the heavy load of sediments flowing into Pamlico Sound. SeaWiFS captur
104763
well, i do know there's this blue chemical called biochemical oxygen demand(BOD) which is used to see how polluted water is from different sources. like, if you compare drain water and pond water. so if you put few drops in each water, and wait for one day, you'll realise that drain water isnt as blue as pond water coz drain water is more polluted. since there are more waste compared to pond water, so there'll be less oxygen. so yeah.
64876
Buoyancy is simple.  If the weight of the liquid moved by insertion of an object into the liquid is greater than the weight of the object, it will float.  That is why the size of ships are measured in displacement.  The "Displacement" refers to the weight of water that is "moved out of the way".\n\nThink of it this way - take two identical spheres with the exact same outer material and thinkness.  One is hallow, and one is filled with lead.  Of course, we know that the one filled with lead will sink?  Why?  Because it weighs more than the water that is being moved out of the way.  How do you make it neutrally bouyant?  Simply fill it with enough lead that equals the weight of the water displaced by the sphere.\n\nThis is called Archimedes Law of Bouyancy.  Google/Yahoo search it and you should find some illustrations to help explain.
892999
WindWalker's statement that oxygen is necessary for the synthesis of nutrients we need is a little misleading.  Oxygen is basically the end of the electron transport chain, and binds hydrogens that have passed though the ion gradient of the mitochondiral matrix to form water.\n\nHydrogen passes through this gradient in the mitochondrial matrix via passive, channel mediated transport.  The concentration of H+ on one side is high, and low on the other, since they get bound to Oxygen to form water.  Every time an H+ ion passes through, energy for ATP production is derived.