Chemistry of snow
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Artificial snow is used on ski slopes, in movies, and for decorating. It is made through specialized "snow guns" that pump water just above its freezing point through nozzles with high pressure. This is accompanied by compressed air which helps lower the temperature, spreading the water into small droplets over a large area. Nucleation agents like clay particles or bacteria provide sites for the water droplets to freeze into snowflakes before falling to the ground, replicating the effect of natural snowfall. This artificial snow production allows ski resorts to have snow year-round.
Chemistry of snow
- 2. Artificial snow is used on ski slopes, movie sets and decorating. Artificial snow for ski slopes creates the same ski effect as natural snow does Brian Rohrig said that, more artificial snow falls on ski slopes than natural snow.
- 3. Snow made for ski slopes is made through essentially a snow gun The first step is to pump water right above its freezing point through the gun with high pressure Secondly, the gun has to give off some kind of nucleation site for the water to adhere too such as clay or dust particles
- 4. Natural snow forms when liquid particles freeze as they fall to the ground The water undergoes deposition, turning from a liquid straight to a solid This is the opposite of sublimation which we studied earlier this year Scientists have tried to duplicate this process through artificial snow
- 5. The first and most important aspect of making this snow is having the correct humidity and the right temperature The process begins with the water right above its freezing point being shot out of the gun nozzle 20- 30 feet above the ground
- 6. While the water is being shot out, it is accompanied by compressed air This makes the water spread into small droplets and spreads them over a larger area The compressed air also helps lower the temperature because when gases expand the temperature lowers This happens because gases have weak attractive forces between their molecules and when the molecules are pushed farther apart they lose their kinetic energy
- 7. Depending on the temperature (15-20 degrees F), organic materials such as magnesium, calcium or clay particles can serve as nucleation sites If it isn't cold enough, inorganic materials such as silver iodide, soaps and detergents are used to help the snow form Once the water molecules adhere to the nucleation sites, the snow falls to the ground
- 8. A newer technology are machines that have nucleating agents in them that is produced with the water The agents are dead, nonpathogenic bacteria that is cultured, freeze dried into pellets and finally sterilized This process is becoming popular because it produces no pollution and is all natural
- 9. Formation of artificial snow enables ski resorts to have snow year round This directly affects the economy in those parts of the world The need for artificial snow to be made is the absence of deposition Snow isnt only important to ski slopes, but to movie makers to make scenes more life-like
- 10. Ritter, Steve. "Artificial Snow." The Newsmagazine of the Chemical World 19 Jan. 2004: 72. Chemical and Engineering News. Web. 10 Apr. 2013. <http://pubs.acs.org/cen/whatstuff/stuff/8203sno w.html>. Rohrig, Brian. "Artificial Snow Powder for the Slopes." ChemMatters Dec. 2000: 10-11. Print. American Chemical Society. "Artificial Snow Creates Winter All Year Round." ScienceDaily, 20 Jan. 2004. Web. 10 Apr. 2013.