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F is a natural trace radioisotope produced by cosmic ray spallation of atmospheric argon as well as by reaction of protons with natural oxygen: 18 O + p → 18 F + n. [53] Other radioisotopes have half-lives less than 70 seconds; most decay in less than half a second. [ 54 ]
Out of the four stable halogens, only fluorine and chlorine have reduction potentials higher than that of oxygen, allowing them to form hydrofluoric acid and hydrochloric acid directly through reaction with water. [17] The reaction of fluorine with water is especially hazardous, as an addition of fluorine gas to cold water will produce ...
Reactions with elemental fluorine are often sudden or explosive. Many substances that are generally regarded as unreactive, such as powdered steel, glass fragments, and asbestos fibers, are readily consumed by cold fluorine gas. Wood and even water burn with flames when subjected to a jet of fluorine, without the need for a spark. [12] [13]
The most reactive metals, such as sodium, will react with cold water to produce hydrogen and the metal hydroxide: 2 Na (s) + 2 H 2 O (l) →2 NaOH (aq) + H 2 (g) Metals in the middle of the reactivity series, such as iron , will react with acids such as sulfuric acid (but not water at normal temperatures) to give hydrogen and a metal salt ...
Since the pressure of the standard formation reaction is fixed at 1 bar, the standard formation enthalpy or reaction heat is a function of temperature. For tabulation purposes, standard formation enthalpies are all given at a single temperature: 298 K, represented by the symbol Δ f H ⦵ 298 K.
The tea plant (Camellia sinensis L.) is a known accumulator of fluorine compounds, released upon forming infusions such as the common beverage. The fluorine compounds decompose into products including fluoride ions. Fluoride is the most bioavailable form of fluorine, and as such, tea is potentially a vehicle for fluoride dosing. [29]
The reaction of F 2 with organic compounds is, however, highly exothermic and can lead to non-selective fluorinations and C–C cleavage, as well as explosions. [6] Only a few selective radical fluorination methods have been reported. [7] [8] The use of fluorine for radical fluorination is mainly limited to perfluorination reactions. [5]
Laboratory setup for fluorine reactions, University of Freiburg. Fluorine gas may be stored in steel cylinders where the inside surface is passivated by a metal fluoride layer that resists further attack. [35] [4] Passivated steel will withstand fluorine provided the temperature is kept below 200 °C (392 °F). Above that temperature, nickel is ...