how does water "disappear"?
930166
Even so water will still evaporate over time if it is in a room with a  high temperature. To obviously stupid answer is somebody drank it!!!
956501
Air, being in solution, is lost all the time at the top of the glass of water and nobody is aware of it.  Air particles by the same effect tend to break away from the water body at the glass sides and bottom.  Contrary to the top, there is a glass barrier, and air particles simply cluster together as small bubbles.  These bubbles of course become bigger with time and some become big enough to break away and float up to the surface.  This effect is much more apparent if you heat the water lightly as the air in solution expands.
222634
Tap water evaporates as it sits around.  The additives become more concentrated as the water evaporates but they don't dissipate.  Eventually they "precipitate" as salts and end up as solids in the container.
615923
you either urinate it out or you crap it out.  The water content can also leave your body by your poars in your skin and it evaporates into the air.
431107
Just the water evaporates leaving behind the salt.  Some places along the Mediterranean they have a process that the salt water goes though leaving behind the salt that we use.  They have several locks that the salt water drain from and finally ends up as a pile of salt to be processed.\nOh by the way clouds don't melt.  The water vapors get heavy until they're so heavy the the water drop as rain droplets.No they do not mix into a different form of water.\nNO! NO! NO! to all the rest of your question.\nChuck
925123
if the water is at very very low pressure it can become gaseous.\n\nSee also - the triple point of water
1042343
Lakes don't hold water... \nLakes happen because the water coming into the lakes through streams, springs, rivers and run-off is in balance with the amount of water being lost from the lake as rivers further downstream, seepage through the ground and evaporation of vapour into the air.\nYou dig a hole in the ground and fill it up, it will lose the water as it drains away, but if you put a hose into it with a steady supply of water, the water appears as if it is not going anywhere.. VOILA.. you have built a lake!!!\n\nAnd.. BY THE WAY.. WEIRD DUDE.. really.. go get a life.. This person asked a fair question and deserved a fair answer..
27398
You can observe this yourself by breathing on a mirror. As the condensation evaporates from the mirror, you have completed the water cycle. Water evaporates into the atmosphere from the ocean, lakes, rivers, and from soil and plants, and even from your skin and breath. When the air reaches saturation (100% humidity) due to cooling or changes in atmospheric pressure (or both) the water condenses  from vapor to liquid (or solid) and falls to earth as rain, snow, sleet, hail, or maybe only as dew. This water may then form streams and rivers and return to the ocean where it may evaporate again into the atmosphere or it may sink into the earth where it becomes groundwater that may take many thousands of years to emerge again, or may be pumped to the surface from a well and used for drinking water or irrigation. It is a continuous cycle that may take only seconds or may take thousands of years to complete the cycle depending on the path of the water.   \n\nWhy do I get the feeling I'm answering your homework question? Now if you'd asked about delta O18 (a heavy isotope of oxygen) I could have told you how the water cycle concentrates water composed of hydrogen and heavy oxygen atoms and how this is used to study paleoclimates using ice cores and sea shells. Have a good day.
792394
Because although the temperature is very low, the pressure is essentially zero (<< 1Pa). Nothing to do with gravity.\n\nReducing pressure reduces the boiling point.\nHowever below T=273K ,P=10^3 Pa, water goes cannot exist as liquid, it goes directly from ice to vapor.\nThis is what the phase diagram of water describes (see graph):\nhttp://en.wikipedia.org/wiki/Phase_diagram\n\nSo the water will evaporate and then sublime to ice almost immediately as its temperature goes below 200K.\nThe ice is going to be in form of microscopic dust because the vapor molecules dispersed due to the zero pressure.\n\nThis diagram is actually clickable, so you can click on the phases and phase lines to see their curve-fit and coefficients.\nIn this case, go to bottom left (low P, low T) you can see the ice-vapor line from (P=0,T=200K) to (P=10^3Pa,T=273K)..\nhttp://www.lsbu.ac.uk/water/phase.html
712828
Water vapor in the air condense on the surface of the glass.  \n\nWater vapor has enough energy to be suspended in air, like clouds.  If the water vapor cools down (loses energy) it turns from gas (vapor) to liquid (like when it rains).
993848
Water is a very unusual substance. When it becomes a solid and crystallizes. The structure of the ice crystal become less dense and floats. The crystalline structure actually pushes the water molecules away from each other and thus expands. This is very unusual because water is one of the only (if not the only) substance that floats as a solid when it is within its on liquid (if that make any sense). So, in an unconfined area, such as a glass of ice water, you would see that the ice floats and rises above the water. In an confined area, such as a bottle, the Ice has no place to go so it expands the bottle. When you let a little of the ice melt and the is some water in the bottle, the bottle is still under pressure from the ice and the water will come out. To prove this, go ahead and freeze a bottle of water, then let it thaw completely; if there is no ice in the bottle, then the water will not come out. It only come out due to the expansion of the ice.
530819
Com'on people, you should know this.\n\nPut in the ice cube slowly, some water spills out, most of the ice is under water (about 92% due to lower density).  Ice melts in time and the water level drops very slightly due to: 1) water temperature drops a bit (higher density, lower volume), 2)evaporation.
470292
When sun shines on water, it warms it up and since heat is lighter, the water kinda floats up into the air. That's called evaporating. Then when it's high in the sky, many little water droplets come together and from clouds. When there's too many water droplets, the cloud becomes to watery and it rains. Then it starts all over again.
653947
When the water supply evaporates.
444674
if you drop something in the water, it displaces water, and that displaced water moves other water, the rock going down in teh water pushes some up, which then pushes some down, and so on and so on.
488884
There are two different "environmental conditions" which would affect the water: very low pressure and very low temperature.\nThe first thing to happen is that the water would "boil" (that is start to turn into a vapor).  This would be described as a "vacuum distillation."  This process (which removes heat from the liquid water), combined with the already low temperature would remove enough heat for the water to freeze.\nIf the container was allowed to remain exposed, the solid water would slowly continue to "sublime" (turn into a vapor under reduced pressure) until some sort of equilibrium was reached.\nNo.  I do not believe that this experiment has been tried, or if tried, the results released to the general public.
628632
the water is warmer then the air and it works the same way breath on a glass window fogs up. the moisture in the air condenses and rises, but this only happens when it is cold or early morning, only when the air is colder then the water.