How come water turns white when it freezes?
457329
This has to do with the optical properties of water as it enters a new so-called phase; from liquid to solid. The liquid and solid state of water are two macroscopic phases, which means that the collective behaviour of the water molecules changes drastically as the temperature, in this case, drops below T = 0 degrees Celsius. As the molecules behave differently in the solid state than in the liquid state, e.g. they reflect light in a different manner due to their structural arrangement, it is not surprising that water has a different color when it freezes compared to when it is a liquid.
415970
I don't have a scientific answer for you, except to say that's just how it works. You could say it's the same reason that water expands when it freezes, as opposed to almost everything else which contracts.
250157
This is due to hydrogen bonds forming between the water molecules, which line up molecules less efficiently (in terms of volume) when water is frozen.
338330
The answer to this is made tougher by the fact that the water will be freezing.  I mean how can you answer a question where the water is ice cold and use the data provided at STP?  Think you need to either re-read your question or provide a little more info.
499459
A very good question.\n\nAlmost all common chemical will contract upon freezing, but not water. \nThe special hydrogen bonding that forces the water molecule to be very close to eacher other in liquid phase.\n\nThe molecule of HOH is not straight, but in a V shape. About 105 degree.\nIn liquid phase the V shape can over lap each other. Go look up the water structure at\nhttp://www.chem1.com/acad/sci/aboutwater.html\n\nDuring freezing, the water molecule are force to line up, and the V shape molecule are line up side by side and no longer over lap.  This takes more room. So it expands.\n\nGo look up the ice molecule structure at http://www.uwgb.edu/dutchs/PETROLGY/Ice%20Structure.HTM\n\nIts not easy to see the true structure, but these will at least gives you a picture.\n\nKeep asking questions, enjoy.
899981
This is what happens if you start freezing a glass of sea water: it will start to freeze at a lower temperature than fresh water (around -4 C, but variable depending on the salinity you start with). \nImportant, the salinity of the ice formed is almost pure water (it is not salty). Some salty water may be trapped on the ice though, but the ice itself is fresh water. If you keep lowering the temperature, more ice will form and the remaining salty water gets even saltier. This process will continues until an eutectic is reached and then you will have a fast crystallization of ice, a mineral called hydrohalite. This eutectic is about -21 C, but depends on other components, like Mg, Ca that are also abundant in the composition of sea water.
21452
Snow is actually clear like ice in a tray. Snow is simply a smaller version of that. It only appears white because of its small particles of ice and light reflection. there is always light reflecting even at night so the snow will still appear to be white.
868477
water freezes at 32 degrees Fahrenheit, and 0 degrees Celsius\n\nthe colder the faster
913491
Well snow is white because it is a frozen sliver of moisture.We christians accept white as a sign of purity.Interestingly if you watch snow falling,no two particles ever collide(till they reach the ground)If you stand underneath falling snow and look directly up,the falling snow won't look white(try it)
713171
No the molecules still weigh the same. With water the volume will increase, that's why ice floats. Most other substances decrease as they freeze.
95097
If you look at an individual snowflake you will find that the frozen water it contains is quite clear. It is only snow in drifts that looks white. Why? Because snow in drifts is  made up of millions of tiny pieces of ice.\n\n\nEvery time light passes from one substance to another rit changes direction. So when you see something underwater it looks like it’s in a different place to where it is because the light has changed direction moving from the water to the air.\n\nWhen light changes direction like that it also gets split up into different colours  a bit, just like if it had passed through a prism.  It isn’t split as completely as if it has passed through a prism, but the blue light gets split out just a bit more than the red. And every time it changes direction it gets split more and more.\n\n\nWhen light passes through a snow drift it will change direction every single time it shines into every individual snowflake. So light shining on a snowdrift changes direction millions of times. And every time it changes direction it gets split up a bit more. By the time it has shone right through the drift it has changed direction so many times that it has completely split into all the separate colours.\n\nWhen your eyes see an object that is producing light in al the different colours at once it registers that as white. And because the light shining through a snowdrift been split into all the different colours the snow becomes white.\n\nIce on a stream or lake on the other hand is a single block, not millions of pieces like a snowdrift. When light shines through a block of ice it changes direction just twice: once when it enters the ice and once when it leaves it. It doesn’t change direction often enough to get split up very much, so the light coming though looks normal, and not white. The ice appears clear.
1032082
Well, snow is frozen water, like ice cubes, which are sometimes white depending on how they freeze.\n\nWhat you see is white are actually snowflakes or snow crystals all piled up together.  They're white because of the way the sun reflects off of them.\n\nWhen they melt they return to water, which doesn't reflect the sun the same way, so you don't see any more white.
1106588
Normally at 0ºC or 32ºF.  At that point water just begins to crystalize.\n\nThere are cases when water will not freeze, like \n- freezing point depression due to hydration,\n- freezing point depression due to osmotic effects (these are both equilibrium effects),\n- supercooling: the delay or absence of formation of an ice crystal in the absence of efficient ice nucleators and/or\n- the high viscosity\n\nFor every 0.5ºC (1ºF), water's viscosity will change by about 1.5%.\n\nWater viscosity is inversely related to temperature. The lower temperature, the higher viscosity.\n\nBut, water's dynamic viscosity at 0ºC is 3.732µ [ 10-5 (lb.s/ft2)] and the kinematic viscosity is 1.924v [10-5 (ft2/s)].
50088
During the winter, the air is colder, but the ground (at least deep down) stays pretty much the same temperature.  Therefore, in a lake, the cold is coming from the top.  This usually freezes the top layer of the lake, which also shields the lower part from freezing - it is now insulated from the weather.  It is very important that ice floats over water, because this allows the ice to make a separation and enables the fish and wotnot to survive the winter.
917405
You mean white, right? Snow reflects light and light's prism makes white, so when the snowflakes change shape into water, they no longer reflect or refract.
153150
the white is because of the lights reflection off of the ice crystals.  When it melts there are no more crystals to reflect.
164824
Huh? Is that english?\n\nOK - I'll make an assumption, something I HATE to do, but I'll assume you are asking about how freezing something effect it's valume and/or mass.\n\nWater for instance... when it freezes, the molecules line up to create a honeycomb pattern, thusly increasing the size of it's mass... increasing volume. Therefore, if you freeze water in a glass, the glass will burst.