FACTOID # 12: It's not the government they hate: Washington DC has the highest number of hate crimes per capita in the US.
 
 Home   Encyclopedia   Statistics   States A-Z   Flags   Maps   FAQ   About 
   
 
WHAT'S NEW
 

SEARCH ALL

FACTS & STATISTICS    Advanced view

Search encyclopedia, statistics and forums:

 

 

(* = Graphable)

 

 


Encyclopedia > Hydrofluoric acid
Hydrofluoric acid
Other names fluoric acid; fluohydric acid
Identifiers
CAS number 7664-39-3
RTECS number MW7875000
Properties
Molecular formula HF(H2O)x
Molar mass not applicable
(see hydrogen fluoride)
Appearance Colorless solution
Density 1.15 g/mL (for 48% soln.)
Melting point

not applicable
(see hydrogen fluoride) Image File history File links Hydrofluoric_acid. ... Image File history File links Download high resolution version (1100x887, 174 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Hydrofluoric acid Hydrogen fluoride ... CAS registry numbers are unique numerical identifiers for chemical compounds, polymers, biological sequences, mixtures and alloys. ... RTECS, also known as Registry of Toxic Effects of Chemical Substances, is a database of toxicity information compiled from the open scientific literature that is available for charge. ... A chemical formula is a concise way of expressing information about the atoms that constitute a particular chemical compound. ... Molar mass is the mass of one mole of a chemical element or chemical compound. ... Hydrogen fluoride is a chemical compound with the formula HF. Together with hydrofluoric acid, it is the principal industrial source of fluorine and hence the precursor to many important compounds including pharmaceuticals and polymers (e. ... For other uses, see Density (disambiguation). ... The melting point of a crystalline solid is the temperature range at which it changes state from solid to liquid. ... Hydrogen fluoride is a chemical compound with the formula HF. Together with hydrofluoric acid, it is the principal industrial source of fluorine and hence the precursor to many important compounds including pharmaceuticals and polymers (e. ...

Boiling point

not applicable
(see hydrogen fluoride) Italic text This article is about the boiling point of liquids. ... Hydrogen fluoride is a chemical compound with the formula HF. Together with hydrofluoric acid, it is the principal industrial source of fluorine and hence the precursor to many important compounds including pharmaceuticals and polymers (e. ...

Solubility in water Miscible.
Acidity (pKa) 3.15 (in water)
Hazards
MSDS External MSDS
Main hazards Toxic, corrosive.
NFPA 704

Solubility is a chemical property referring to the ability for a given substance, the solute, to dissolve in a solvent. ... Impact from a water drop causes an upward rebound jet surrounded by circular capillary waves. ... The chemistry term miscible refers to the property of various liquids that allows them to be mixed together. ... The acid dissociation constant (Ka), also known as the acidity constant or the acid-ionization constant, is a specific equilibrium constant for the reaction of an acid with its conjugate base in aqueous solution [1]. // When an acid dissolves in water, it partly dissociates forming hydronium ions and its conjugate... Impact from a water drop causes an upward rebound jet surrounded by circular capillary waves. ... An example MSDS in a US format provides guidance for handling a hazardous substance and information on its composition and properties. ... External link DuPont Material Safety Data Sheet by DuPont Fluoroproducts ... The examples and perspective in this article or section may not represent a worldwide view. ... NFPA 704 is a standard maintained by the U.S. National Fire Protection Association. ... Image File history File links NFPA_704. ...

0
4
1
 
R-phrases R26/27/28, R35
S-phrases (S1/2), S7/9, S26, S36/37, S45
Flash point nonflammable
Related Compounds
Other anions Hydrochloric acid
Hydrobromic acid
Hydroiodic acid
Related compounds Hydrogen fluoride
fluorosilicic acid
Supplementary data page
Structure and
properties
n, εr, etc.
Thermodynamic
data
Phase behaviour
Solid, liquid, gas
Spectral data UV, IR, NMR, MS
Except where noted otherwise, data are given for
materials in their standard state
(at 25 °C, 100 kPa)

Infobox disclaimer and references

Hydrofluoric acid is a solution of hydrogen fluoride in water. Together with hydrogen fluoride, hydrofluoric acid is a valued source of fluorine, being the precursor to numerous pharmaceuticals, diverse polymers (e.g. Teflon), and most other synthetic materials that contain fluorine. Hydrofluoric acid is best known to the public for its ability to dissolve glass by reacting with SiO2, the major component of most glasses. This dissolution process can be described as follows: R-phrases are defined in Annex III of European Union Directive 67/548/EEC: Nature of special risks attributed to dangerous substances and preparations. ... S-phrases are defined in Annex IV of European Union Directive 67/548/EEC: Safety advice concerning dangerous substances and preparations. ... For other uses, see Flash point (disambiguation). ... This article is about the electrically charged particle. ... R-phrases , S-phrases , , Flash point Non-flammable. ... It has been suggested that this article or section be merged into hydrogen bromide. ... Hydroiodic acid (sometimes also spelled hydriodic acid) is a highly acidic aqueous solution of hydrogen iodide (HI) (Concentrated solution is usually 48 - 57% HI). ... Hydrogen fluoride is a chemical compound with the formula HF. Together with hydrofluoric acid, it is the principal industrial source of fluorine and hence the precursor to many important compounds including pharmaceuticals and polymers (e. ... Hexafluorosilicic acid is the chemical compound with the formula H2SiF6. ... External link DuPont Material Safety Data Sheet by DuPont Fluoroproducts ... External link DuPont Material Safety Data Sheet by DuPont Fluoroproducts ... The refractive index (or index of refraction) of a medium is a measure for how much the speed of light (or other waves such as sound waves) is reduced inside the medium. ... The relative dielectric constant of a material under given conditions is a measure of the extent to which it concentrates electrostatic lines of flux. ... External link DuPont Material Safety Data Sheet by DuPont Fluoroproducts ... External link DuPont Material Safety Data Sheet by DuPont Fluoroproducts ... Ultraviolet-Visible Spectroscopy or Ultraviolet-Visible Spectrophotometry (UV/ VIS) involves the spectroscopy of photons (spectrophotometry). ... Infrared spectroscopy (IR spectroscopy) is the subset of spectroscopy that deals with the infrared region of the electromagnetic spectrum. ... Nuclear magnetic resonance spectroscopy most commonly known as NMR spectroscopy is the name given to the technique which exploits the magnetic properties of certain nuclei. ... Mass spectrometry (previously called mass spectroscopy (deprecated)[1] or informally, mass-spec and MS) is an analytical technique used to measure the mass-to-charge ratio of ions. ... The plimsoll symbol as used in shipping In chemistry, the standard state of a material is its state at 1 bar (100 kilopascals exactly). ... Making a saline water solution by dissolving table salt (NaCl) in water This article is about chemical solutions. ... Hydrogen fluoride is a chemical compound with the formula HF. Together with hydrofluoric acid, it is the principal industrial source of fluorine and hence the precursor to many important compounds including pharmaceuticals and polymers (e. ... Impact from a water drop causes an upward rebound jet surrounded by circular capillary waves. ... In chemistry, polytetrafluoroethylene (PTFE) is a synthetic fluoropolymer which finds numerous applications. ... This article is about the material. ...

SiO2(s) + 4HF(aq)SiF4(g) + 2H2O(l)
SiO2(s) + 6HF(aq)H2[SiF6](aq) + 2H2O(l)

Because of its high reactivity toward glass, hydrofluoric acid is typically stored in polyethylene or Teflon containers. It is also unique in its ability to dissolve many metal and semimetal oxides. It is extremely corrosive, as explained below:- R-phrases R42 R43 R49 S-phrases S22 S36 S37 S45 S53 Flash point non-flammable Supplementary data page Structure and properties n, εr, etc. ... Silicon tetrafluoride is the chemical compound with the formula SiF4. ... Impact from a water drop causes an upward rebound jet surrounded by circular capillary waves. ... Dihydrogen hexafluorosilicate is commonly used for Water fluoridation in the United States. ... This article does not cite any references or sources. ... In chemistry, polytetrafluoroethylene (PTFE) is a synthetic fluoropolymer which finds numerous applications. ... This article is about metallic materials. ... Together with the metals and nonmetals, the metalloids (in Greek metallon = metal and eidos = sort - also called semimetals) form one of the three categories of chemical elements as classified by ionization and bonding properties. ... An oxide is a chemical compound containing at least one oxygen atom and other elements. ...

Contents

Acidity

Hydrogen fluoride dissociates in aqueous solution in a similar fashion to other common acids:

HF + H2O → H3O+ + F

When the concentration of HF approaches 100%, the acidity increases dramatically due to the following equilibrium:

2HF → H+ + FHF

The FHF anion is stabilized by the very strong hydrogen - fluorine hydrogen bond. In acetic acid and similar solvents, hydrofluoric acid is the strongest of the hydrohalic acids. The hydrogendifluoride anion The hydrogendifluoride ion is the hydrogen-bonded anion [HF2]−. It can be considered as a molecule of HF that is hydrogen bonded to an F− ion: [F−H···F]−. There is a high degree of covalency in this particularly strong hydrogen bond, and both F−H distances... An example of a quadruple hydrogen bond between a self-assembled dimer complex reported by Meijer and coworkers. ...


Production

Main article: hydrogen fluoride

Industrially, hydrofluoric acid is produced by treatment of the mineral fluorite (CaF2) with concentrated sulfuric acid. When combined at 250 °C, these two substances react to produce hydrogen fluoride according to the following chemical equation: Hydrogen fluoride is a chemical compound with the formula HF. Together with hydrofluoric acid, it is the principal industrial source of fluorine and hence the precursor to many important compounds including pharmaceuticals and polymers (e. ... Fluorite (also called fluor-spar) is a mineral composed of calcium fluoride, CaF2. ... R-phrases S-phrases , , , Flash point Non-flammable Related Compounds Related strong acids Selenic acid Hydrochloric acid Nitric acid Related compounds Hydrogen sulfide Sulfurous acid Peroxymonosulfuric acid Sulfur trioxide Oleum Supplementary data page Structure and properties n, εr, etc. ... A chemical equation is a symbolic representation of a chemical reaction. ...

CaF2 + H2SO4 → 2HF + CaSO4

Calcium sulphate is a common laboratory and industrial chemical. ...

Uses

Because of its ability to dissolve metal oxides, hydrofluoric acid is used in the purification of both aluminium and uranium. It is also used to etch glass, to remove surface oxides from silicon in the semiconductor industry, as a catalyst for the alkylation of iso-butane and butene in oil refineries, and to remove oxide impurities from stainless steel in a process called pickling. Dilute hydrofluoric acid is sold as a household rust stain remover. Recently it has even been used in car washes in "wheel cleaner" compounds.[1] Due to its ability to dissolve silicate compounds, hydrofluoric acid is often used to dissolve rock samples (usually powdered) prior to analysis. Aluminum redirects here. ... This article is about the chemical element. ... This article is about the material. ... Not to be confused with Silicone. ... A semiconductor is a solid whose electrical conductivity is in between that of a conductor and that of an insulator, and can be controlled over a wide range, either permanently or dynamically. ... Butylene, also known as butene, is the name of the three isomeric hydrocarbon gases with chemical formula C4H8. ... View of the Shell/Valero Martinez oil refinery An oil refinery is an industrial process plant where crude oil is processed and refined into useful petroleum products. ... The 630 foot (192 m) high, stainless-clad (type 304) Gateway Arch defines St. ... For other uses, see Car wash (disambiguation). ...


Hydrofluoric acid is also used in the synthesis of many fluorine-containing organic compounds, including Teflon,fluoropolymers, perfluorocarbons and refrigerants such as freon. Distinguished from fluorene and fluorone. ... In chemistry, polytetrafluoroethylene (PTFE) is a synthetic fluoropolymer which finds numerous applications. ... A fluoropolymer is a polymer that contains atoms of fluorine. ... Fluorotelomer alcohol FTOH 8:2 Perfluorocarbons (PFCs) are compounds derived from hydrocarbons by replacement of hydrogen atoms by fluorine atoms. ... Refrigeration is the process of removing heat from an enclosed space, or from a substance, and rejecting it elsewhere for the primary purpose of lowering the temperature of the enclosed space or substance and then maintaining that lower temperature. ... Freon is a trade name for a group of chlorofluorocarbons used primarily as a refrigerant. ...


Safety

Symptoms of skin exposure to dilute HF are not felt immediately, but can be fatal. Highly concentrated solutions may lead to acute hypocalcemia, followed by cardiac arrest and death. This will usually be fatal in as little as 2% body exposure (about the size of the sole of the foot). This substance should be handled with extreme care, beyond that accorded to hydrochloric, sulfuric, or other mineral acids. Image File history File links Skull_and_crossbones. ... Image File history File links Skull_and_crossbones. ... Wikipedia does not have an article with this exact name. ... Wikipedia does not have an article with this exact name. ... In medicine, hypocalcaemia is the presence of less than a total calcium of 2. ...


Due to low dissociation constant, HF can penetrate tissues quickly. Hydrofluoric acid which comes into direct contact with the fingers can severely damage or destroy the tissue underneath the nail without causing any damage to the nail itself. It is this ability to cause little harm to outer tissues but considerable harm to inner tissues which can produce dangerous delays in treatment of hydrofluoric acid exposure. Once the pain starts, it is out of proportion to the burns produced. Patients often describe the feeling as if they have struck their fingers with a hammer. HF that penetrates under the skin causes later development of painful ulcers, which heal slowly.


Solutions of less than 20% HF can produce pain and redness with delay up to 24 hours after skin exposure. 20 to 50% HF produces pain and redness within 8 hours, and solutions of more than 50% produce immediate burning, redness and blister formation. Contact of the skin with the anhydrous liquid produces severe burns.[citation needed]

Calcium gluconate is used to treat hydrofluoric acid exposure
Calcium gluconate is used to treat hydrofluoric acid exposure

In the body, hydrofluoric acid reacts with the ubiquitous ions of calcium and magnesium and so can disable tissues and organs whose proper function depends on these metal ions. Exposure to hydrofluoric acid may not be initially painful, and symptoms may not occur until several hours later, when the acid begins to react with calcium in the bones. Under most circumstances, hydrofluoric acid exposure results in severe or even lethal damage to the heart, liver, kidneys, and nerves. Initial treatment to hydrofluoric acid exposure usually involves thorough rinsing (for up to 15 minutes) of to the exposed areas followed by the application of calcium gluconate gel. If exposure is high, or too much time has passed, a calcium gluconate solution may be injected directly into a local artery or surrounding tissues. In all cases, hydrofluoric acid exposure requires immediate professional medical attention. If coming in contact with human skin or bone the acid can severely burn and then decompose the bone, potentially necessitating amputation of the affected limbs. Image File history File links Download high-resolution version (1100x565, 179 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Hydrofluoric acid ... Image File history File links Download high-resolution version (1100x565, 179 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Hydrofluoric acid ... This article is about the electrically charged particle. ... For other uses, see Calcium (disambiguation). ... General Name, symbol, number magnesium, Mg, 12 Chemical series alkaline earth metals Group, period, block 2, 3, s Appearance silvery white solid at room temp Standard atomic weight 24. ... The heart and lungs, from an older edition of Grays Anatomy. ... For the bird, see Liver bird. ... The kidneys are the organs that filter wastes (such as urea) from the blood and excrete them, along with water, as urine. ... Nerves (yellow) Nerves redirects here. ... Calcium lactate gluconate is a soluble salt often used in effervescent calcium tablets. ... Calcium lactate gluconate is a soluble salt often used in effervescent calcium tablets. ... Partial hand amputation Amputation is the removal of a body extremity by trauma or surgery. ...


The highest concentration of HF in air that can be tolerated by a human for 1 minute is 100 mg/m3.[citation needed] This causes a definite sensation of pain on the skin, a definite sour taste, and some degree of eye and respiratory irritation[citation needed]. If the air contains 50 mg/m3, the sour taste is apparent and there is irritation of the eyes and nose, but no pain is sensed on the skin[citation needed]. The concentration of 26 mg/m3 can be tolerated for several minutes, but the sour taste becomes evident after a short time, and there is mild pain in the nose and eyes[citation needed]. The American Conference of Governmental Industrial Hygienists has adopted 2 mg/m3 as the threshold limit for hydrogen fluoride. This comes to about 3 ppm (parts per million). Inhalational exposure to concentrated HF for as little as 5 minutes is usually fatal, producing death within 2-10 hours.[citation needed]


A concern for emergency services is the theft of drums of hydrofluoric acid, possibly after being mistaken for hydrochloric acid which has uses in the preparation of all kinds of substances, including in the clandestine production of drugs such as methamphetamines. A young waif steals a pair of boots “Stealing” redirects here. ... R-phrases , S-phrases , , Flash point Non-flammable. ... This article is about the psychostimulant, d-methamphetamine. ...


Hydrofluoric acid is a known hazard in car engine fires, forming when Viton o-rings and hoses are exposed to temperatures in excess of 400 °C. Viton® is a synthetic rubber and fluoropolymer elastomer commanly used in o-rings. ... Typical O-ring and application An O-ring is a loop of elastomer with a round (o-shaped) cross-section used as a mechanical seal. ... Look up hose in Wiktionary, the free dictionary. ...


If the propellant from canned air which has Tetrafluoroethane is ignited, or exposed to an open flame it can lead to amounts of Hydrofluoric Acid in the air. Tetrafluoroethane (CH2FCF3, technically 1,1,1,2-Tetrafluoroethane) is an inert gas found in cans of air used for blow-dusting computers and other miscellaneous items that are hard to reach or access. ...


References

  1. ^ Strachan, John (January, 1999). "A deadly rinse: The dangers of hydrofluoric acid". Professional Carwashing & Detailing. Retrieved on 2006-08-30. 

Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 242nd day of the year (243rd in leap years) in the Gregorian calendar. ...

External links

  • International Chemical Safety Card 0283
  • National Pollutant Inventory - Fluoride and compounds fact sheet
  • NIOSH Pocket Guide to Chemical Hazards
  • CID 14917 from PubChem (HF)
  • CID 144681 from PubChem (5HF)
  • CID 141165 from PubChem (6HF)
  • CID 144682 from PubChem (7HF)
  • Computational Chemistry Wiki
  • Hydrofluoric Acid Burn, The New England Journal of Medicine Acid burn case study

  Results from FactBites:
 
Hydrofluoric acid - Wikipedia, the free encyclopedia (872 words)
Due to its ability to dissolve silicate compounds, hydrofluoric acid is often used during the rock and mineral analysis process to dissolve rock samples (usually powdered) prior to analysis.
Hydrofluoric acid is also used in the synthesis of many fluorine-containing organic compounds, including teflon and refrigerants such as freon.
Exposure to hydrofluoric acid may not be initially painful, and symptoms may not occur until several hours later, when the acid begins to react with calcium in the bones.
OHS - Standard Operating Procedure for Using Hydrofluoric Acid (1469 words)
Concentrated hydrofluoric acid is used in the fabrication of electronic components, to etch glass and in the manufacture of semiconductors.
Hydrofluoric acid solutions are clear and colorless with a density similar to that of water.
Hydrofluoric Acid may be used when working alone during normal working hours provided knowledgeable laboratory personnel have been alerted and at least one is in the general vicinity.
  More results at FactBites »

 
 

COMMENTARY     


Share your thoughts, questions and commentary here
Your name
Your comments

Want to know more?
Search encyclopedia, statistics and forums:

 


Press Releases |  Feeds | Contact
The Wikipedia article included on this page is licensed under the GFDL.
Images may be subject to relevant owners' copyright.
All other elements are (c) copyright NationMaster.com 2003-5. All Rights Reserved.
Usage implies agreement with terms, 1022, m