Paris—Henri Moissan elements |
Fluorine
Georgius Agricola used fluorite to lower the melting point of metals during smelting. Andreas Sigismund Marggraf invented hydrofluoric acid. André-Marie Ampère knew hydrofluoric acid contained a new element similar to chlorine. Humphry Davy was poisoned trying to isolate it and named it fluorine. No one could isolate it. It was too reactive. It didn’t conduct electricity so electrolysis failed. It corroded electric terminals. It was so toxic several chemists died of it. Henri Moissan used electrolysis with platinum and iridium terminals in a glass container sealed with fluorite containing a conductive mixture of potassium bifluoride and dry hydrogen fluoride cooled to slow down the corrosion.
Atomic number 9
Fluorite for smelting metals Hydrofluoric acid for etching glass Chlorofluorocarbon for refrigerants Hexafluorosilicic acid for water fluoridation Sodium monofluorophosphate for toothpaste Sodium hexafluoroaluminate and aluminium trifluoride for aluminum extraction Uranium hexafluoride for uranium enrichment Polytetrafluoroethylene for Teflon™ Polytetrafluoroethylene for Gore-Tex® Krypton fluoride for lasers
Unnatural stuff
Stuff that doesn’t form in nature, is it all that unnatural? Even natural stuff—arsenic, lead, mercury—is toxic, so do you want it? Fluorine is corrosive, volatile, and toxic, but there’s no adverse affect of low amounts of calcium fluoride in water. Our town didn’t fluoridate, so we had our dentist give our kid fluoride treatments.
The short history of the Anthropocene epoch includes stories of extreme barbarism, wantonness, and carelessness, but also gradual improvement, in spite of notable disasters, of our ability to control our material environment.
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