Surviving the big chill — In the United States, between 750 and 1,000 people die from hypothermia in the average year. Despite common misperceptions, any air temperature under 60 F has the potential to cause hypothermia. According to a recent article in ChemMatters, a quarterly magazine for high school chemistry students published by the American Chemical Society, survival strategies such as eating snow for water can accelerate hypothermia because the body cannot afford the heat to bring the snow to body temperature and melt the ice crystals. Falling into cold water is especially dangerous because water, which has a great capacity for heat, rapidly drains away heat energy from the body.
What’s that stuff? Aircraft de-icers — If you’re planning to escape south this winter, rest assured chemists have made your travels safer. De-icers such as chloride salts are effective and popular for use on roadways, but they are corrosive and prohibited for use on aircraft. Like automobile antifreeze, aircraft deicing fluids are aqueous solutions of glycol, according an article published in Chemical & Engineering News, a weekly magazine published by the American Chemical Society. Aircraft de-icers break up snow or ice so it can be removed from critical surfaces — such as the wings, flaps, and fuselage — more easily. When a plane is held over for a longer period of time, de-icing is followed by treatment with anti-icing fluid, which keeps water from freezing or refreezing.
Powder for the slopes — More snow falls on ski slopes today from snowmaking machines than from the sky. Real snow is formed when tiny ice crystals adhere to dusty particles in the atmosphere, according to a recent article in ChemMatters. When the particle becomes heavier than the buoyant force of the air holding it up, it falls to the ground as snow. Snowmaking machines mimic the process by sending out a spray of water, compressed air, and dead, nonpathogenic bacteria for ice crystals to build on. The water, shot 20 to 30 feet into the air, turns to snow before it hits the ground.
Editor's note - Please attribute this information to the American Chemical Society if all or any part is used in a print story or a broadcast.
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What's that stuff? Aircraft de-icers