what is the diffusivity of oxygen in water?
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I bet you could look this up on the web pretty easily. Why didn't you try?\n\nI bet the diffusivity is pretty good, however, because otherwise, how could fish breathe?
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You will find the formula you need just over half way down the page:\n\nhttp://en.wikipedia.org/wiki/Speed_of_sound\n\nI get speed of sound is 4 x faster in oxygen than hydrogen (1/sqrt16)
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# 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
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Difusion is the movement of particles from an area of high concentration to an area of low concentration, until they are apread out evenly.\n\nExamples for diffusion: \nThe alveoli are well adapted for diffusion of gases, \nthey have a large surface area\nthey are moist, so gases can dissolve\nthey have thin walls\nand a good blood supply.\n\nThe small intestine is specialised for absorption. \nIt has: \nA thin lining\na good blood supply\na very large surface area.\n\nOsmosis is the diffusion of water molecules from a dilute solution to a more concentrated solution through a partially permeable membrane.\n\nA partially permeable membrane allows water molecules to pass through, but not solute molecules.\n\nWhen a plant cells are full of water they are turgid.\nThis rigidity or turgour gives the plant support\nCells are able to absorb some substances against a concentration gradient.\n\nActive transport needs energy from respiration. \n\nActive transport....\nNot all sustances pass into cells by diffusion or osmosis. Some substances are absorbed against a concentration gradient. But to do this energy is needed and it comes from respiration. This process is called ACTIVE TRANSPORT.\nExample of active transport are:\nThe uptake of ions by root hair cells from the soil, where they are in very dilute solution;\nthe uptake of sugar molecules into the small intestine;\nthe re-absorbtion of useful ions in the nephrons of the kidneys.
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osmosis can occur in the small intestine where water is secreated and absorbed, while diffusion occurs in the lungs where oxygen is diffused into the blood stream and carbon dioxide is excreated from the blood stream to the atmosphere
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Diffusion of a Dye in Hot and Cold Water\n\nPurpose:  The purpose of this experiment is to demonstrate the principle of diffusion.  Diffusion is the net movement of particles (atoms, ions, or molecules) from an area of greater concentration to areas of lesser concentration.\n\nMaterials and Methods:  For this experiment, the student will require a projector, two petri dishes, two 150 ml beakers, hot plate, potassium permanganate (purple dye), and a spatula.  Obtain about 50 ml of cold water in one beaker and about 50 ml or boiling water in the other.  Place the petri dishes on the projector and add cold water to one dish and boiling water to the other.  Allow the water in the dishes to become still.  Using the spatula, add a crystal of potassium permanganate to the center of each dish\n\nExperiment:  Observe the experiment for several minutes and note what happens to the purple dye in each petri dish.\n\nConclusion:  Do you observe diffusion in each?\n\nHow does the rate of diffusion differ? \n\nWhy is there a greater rate of diffusion in one
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Oxygen is carried in the blood.  The oxygen transfers from the atmosphere to your blood through an exchange in your lungs...\n\nA fish's gills accomplish the same thing, but they get the oxygen from the water.
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You need to be a little more specific. Would that be in water quality, oxygen in blood, or soil? To measure water quality they just use dissolved oxygen meter, which exploits the electrochemical properties of the water. Or you could do a Winkler titration.
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That is definitely not correct!!\n\nFor example water (H20) is very very different from the two gases that make it namely hydrogen (H2) and oxygen (O2)
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7.04 grams\n\n15 grams of water is .44 mol and according to the equation, the ratio between water and oxygen is2:1 so if .44 mol of water is decomposed. then .22 mol of oxygen will be produced. and .22 mol of oxygen is .22 *32 =7.04grams
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Water vapor.\n2 H2 + O2 = 2 H2O
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Yes; think of the cell as a sack filled with stuff surrounded by a semipermeable membrane. Water diffuses through the pores based on its concentration. That is, water goes from an area of great to less concentration. Since the distilled water by definition has no solute and is 100 per cent pure and since the concentration of the water in the cell is diluted by the presence of small particles (almost one percent), water flows from the outside to the inside very quickly. The membrane is stretched so much by the infusion of water that it bursts.
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Those 'oxygen enriched water' machines a scam. They are a way to take money off stupid people.\n\nNo, the human body can not absorb the oxygen present in water. Well, that's not quite true. You could absorb the oxygen in water if you breathed it in. Then you would drown. But if you are just drinking the water or bathing in it you can never absorb the oxygen in it.
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Dissolved oxygen levels usually range from 6 to 14 mg/L. \n\nRemember, ambient temperature will have a significant impact on your readings, because the solubility of oxyden in water falls with a rise in temperature. So you'll need to take that into consideration while writing up your findings. \n\nI suggest that you take some readings at different times of the day, to establish a baseline. \n\nHope that helps.
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I'm also amazed at the answers including the preceding one. It's true it's all about bouyancy. But is bouyancy affected significantly by the dissolved oxygen in the tissues? According to the ref., bouyancy is just about lung capacity, bone, fat and muscle ratios. And of course the salinity of the water. Also, panic-induced body tension can reduce lung capacity and muscle performance.  \nAnyway, a change in tissue oxygen level would happen slowly; it's a diffusive process. Second, the density difference of water with and without dissolved oxygen has to be minute since oxygen is only sparingly soluble.
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Here you go:\n\n"Critical oxygen tension is the minimum amount of dissolved oxygen necessary to sustain metabolic processes."\n\nCheers!
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Since the oxygen is collected over water, you must subtract out the water vapor pressure to determine the pressure due to just the oxygen.\n\n722.2 mmHg - 21.1 mmHg = 701.1 mmHg = 0.922 atm due to O2\n\n0.276g KClO3 = 0.00175 moles KClO3 (molar mass = 158 g/mol)\nSince KClO3 decomposes to form O2 in a 2:3 ratio, the number of moles of O2 produced = 0.00262 moles O2\n\nPV=nRT\n(0.922 atm) V  = 0.00262 mol (0.08206)(296.2K)\n\nSolving for the volume due to the O2,  V = 691 mL