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Hydrogen fluoride is typically produced by the reaction between sulfuric acid and pure grades of the mineral fluorite: [14] CaF 2 + H 2 SO 4 → 2 HF + CaSO 4 About 20% of manufactured HF is a byproduct of fertilizer production, which generates hexafluorosilicic acid .
Hydrofluoric acid is a solution of hydrogen fluoride (HF) in water.Solutions of HF are colorless, acidic and highly corrosive.A common concentration is 49% (48-52%) but there are also stronger solutions (e.g. 70%) and pure HF has a boiling point near room temperature.
If HF alone is electrolyzed, hydrogen forms at the cathode (positive part of the cell) and the fluoride ions remain in solution. After electrolysis, potassium fluoride remains in solution. [35] 2 HF 2 − → H 2 ↑ + F 2 ↑ + 2 F −. The modern version of the process uses steel containers as cathodes, while blocks of carbon are used as anodes.
Vapor etching refers to a process used in the fabrication of Microelectromechanical systems (MEMS) and Nanoelectromechanical systems (NEMS). Sacrificial layers are isotropically etched using gaseous acids such as Hydrogen fluoride and Xenon difluoride to release the free standing components of the device.
Hydrogen fluoride [5] References This page was last edited on 22 October 2024, at 07:42 (UTC). Text is available under the Creative Commons Attribution-ShareAlike 4 ...
Fluoroantimonic acid is a mixture of hydrogen fluoride and antimony pentafluoride, containing various cations and anions (the simplest being H 2 F + and SbF − 6).This mixture is a superacid stronger than pure sulfuric acid, by many orders of magnitude, according to its Hammett acidity function.
Hydrogen bonding amongst HF molecules gives rise to high viscosity in the liquid phase and lower than expected pressure in the gas phase. Hydrogen fluoride does not boil until 20 °C in contrast to the heavier hydrogen halides which boil between −85 °C and −35 °C (−120 °F and –30 °F).
Because the fluoride ion is such a strong hydrogen bond acceptor, its salts tend to be hydrated and of limited solubility in organic solvents. As a fluoride ion source, TBAF solves this problem, although the nature of the fluoride is uncertain because TBAF samples are almost always hydrated, resulting in the formation of bifluoride (HF 2 −) hydroxide (OH −) as well as fluoride.