INORGANIC CHEMISTRY A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z                    HOME ABOUT CATEGORIES SITE MAP COPYRIGHT ADVERTISE CONTACT entire Web this site fluorine (F) A pale yellow, highly corrosive, highly poisonous, gaseous element. Fluorine belongs to the halogen family and is the most electronegative and reactive of all the elements. Steel wool bursts into flames when exposed to it. Fluorine is used in a wide variety of industrially important compounds. It was discovered in 1529, but first isolated by Henri Mossian in Paris in 1866. Fluorine salts, known as fluorides, were used for centuries in welding metals and for frosting glass before the element itself was isolated. Fluorine is used to make uranium hexafluoride, needed by the nuclear power industry, and sulfur hexafluoride insulating gas for high-power electricity transformers, and to treat polythene to make it impermeable to solvents. atomic number 9 atomic mass 18.998 electron configuration 1s22s22p5 first ionization energy 1,681 kJ/mol electronegativity 4.0 atomic radius 71 pm ionic radius 136 pm melting point -219.62 °C (-363.32 °F) boiling point -188.14 °C (-307.45 °F) relative density 1.108 Related category    • INORGANIC CHEMISTRY Also on this site: Encyclopedia of Alternative Energy & Sustainable Living Encyclopedia of History Transport Concepts & Designs (partner site) BACK TO TOP