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Calcium Chloride in Bunsen Flame (reaction only)
For all the basics about calcium, check out the Visual Elements Periodic Table.
For more interesting facts and pictures of calcium, check out The Elements by Theodore Gray.
The NAICA Crystal cave is located 300 meters below ground. Filled with enormous, spectacular selenite or moonstone crystals, it reveals its beauty in an atmosphere where its icy appearance contrasts with the high temperatures in the depths. Through the magnificence of its crystals, it leads us down a myriad of paths: scientific, technological, artistic, philosophical and one involving the magic of nature. it also brings us face-to-face with an unavoidable responsibility: our obligation to protect and preserve it.
“Cave of the Crystals” or “Giant Crystal Cave” is a cave in Naica, Mexico, only discovered in 2000 by miners. Within this cave, spectacular selenite crystals (CaSO4·2 H2O) have been formed up to 12 m length, 4m in diameter and weighing 55 tonnes!
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Can you describe some of the problems that hard water can cause in the home and to your health? How can one overcome these problems?
09/24/2013 • 
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