Fluorine, 195 atomic mass reactivity

Elemental fluorine, which is a member of the halogen family, is a pale yellow-green, irritating gas with a sharp odour and atomic mass of 18.998. Fluorine is chemically most reactive of all the elements and does not therefore occur naturally in the free state. In combination it comprises 0.065% of the earth s crust, being the 13th element in abundance [1], and is an inevitable part of the biosphere and human life. The term fluorine is, in this report, used to denote the element in any of its forms and fluoride to denote free inorganic fluoride to which a fluoride ion-selective electrode (ISE) responds. 

DFT calculations for the activation of fluoromethane and fluorobenzene at Ce and Ho have been performed revealing a harpoon-type mechanism for the metal-mediated fluoride abstraction.The reactions of the lanthanoid cations La Ce, Pr, and Yb with fluoromethane have also been investigated by DFT calculations. After coordination of Ln, electron transfer from Ln to fluoromethane takes place, followed by formation of LnF and a methyl radical. Mass spectrometric investigations which show gas-phase collisions of Nb with hexafluoro- and tetrafluorobenzene have been reported. The reaetions involve the transfer of four fluorine atoms to Nb. A systematic study on the reactivity of transition metal eations toward hexafluorobenzene in the gas phase has been performed by inductively coupled plasma (ICP) tandem mass spectrometry.Multiple fluorine atom abstraction dominates the chemistry observed for early transition metals, while association of hexafluorobenzene to the metal cation has been found for late transition metals. 

After the outbreak of World War II in 1939, leading nuclear scientists realized that a new type of weapon was possible, based on atomic fission. A key requirement was the separation of the isotope of mass 235 (only 0.7%) present in natural uranium. By 1941, it was clear that the only practicable process was by gaseous diffusion of uranium(VI) fluoride, the sole compound of sufficient volatility. However, this attacked normal organic materials rapidly, being almost as reactive as elemental fluorine. 

The reactivity of a variety of fluorine-containing olefins with ground-state ( i ) oxygen atoms has been investigated. A study using a discharge flow system coupled to a mass spectrometer has produced the following rates (in 10 cm mol ... 

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