Snow and ice are both made from H2O. So why is ice clear and dense, whereas snow is white and flaky? And how does one create the conditions to turn water into snow rather than ice? Why does water behave in this unusual way? Do other liquids have more than one way of solidifying?
Snow is a lot of tiny ice crystals with air between them. The edges of the crystals reflect light, so snow looks white. An individual snowflake, when magnified, looks clear, as “normal” ice.
As for your last question, every crystal looks different depending on how fine the pieces are. Powdered sugar looks very different from rock candy, even though they are exactly the same chemical. It should also be possible to have transparent salt crystals, but I’ve never seen one.
To answer that question, snow is formed when water vapor freezes directly into a solid, while ice (sleet, hail, etc.) is formed when liquid water freezes.
The Ryan:
I have. I can’t quite remember where or when I found it, but I got my hands on a large salt crystal. It was clear and pointed, like quartz, but when you licked it, it was salty. So yes, a large enough salt crystal is clear.
Salt in the form of large clear crystals is called “halite”.
isn’t time a factor as to whether a substance will crystalize or not? the more time given to cool, the more it will crystalize.
i regretfully didn’t pay much attention in grade 12 geology, but i seem to remember something along these lines.
I think the main item you need in the equation is “wind”; It keeps the water particles moving and seperated when they freeze, where ice is formed as a result of water, en masse, freezing.
yes but water vapor is liquid not gas - so thats the same process as the water freezing in you ice cube tray.
The big diffrence is the size of the water vapor droplets. They are very small and have air around them.
Liquid water droplets (not water vapour) freeze to make snowflakes.
Whoops! Next time I’ll check before I post, not when that nagging doubt creeps in…
hightechburrito is right. Snow crystals form by condensation of vapour onto a solid nucleus at sub-freezing temperatures.
Snow is formed in the clouds. Ice crystals in the clouds coalesce and, when heavy enough, fall as snow. That is the difference. Freezing rain is rain that freezes when it lands. Sleet can be formed by a number of ways: It can begin as snow, but pass thru a warmer layer of air and melt, and then refreeze before it lands. It can also begin as rain, but freezes before it lands, and lands as an ice pellet we call sleet.
Meteorologists have a lot of terms for the different forms snow and sleet can take. I don’t remember all of them. In fact, I can’t remember any of them right now.
Another fallacy is that no two snow flakes are alike. This fallacy was bsed on a study done by someone whose name I also cannot remember. He found no two snowflakes alike. Of course, snowflakes can take many forms: they can be needle-like, crystal-like, and other forms which I also don’t remember. This doesn’t mean, however, that no two flakes cannot be alike. (Snow flakes, I’m talking about.)
I want to say something else. But I can’t remember what it is.