Wikipedia:WikiProject Chemicals/Chembox validation/VerifiedDataSandbox and Fluoroform: Difference between pages

{{Redirect|CHF3|the Transport Canada LID|Westlock (Hnatko Farms) Aerodrome}}

{{Chembox

| Verifiedfields = changed

| Watchedfields = changed

| verifiedrevid = 461102015

| OtherNames = Fluoroform, carbon trifluoride,{{cn|date=August 2023}} methyl trifluoride, Fluoryl, Freon 23, Arcton 1

|Section1={{Chembox Identifiers

| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}

| Abbreviations = HFC 23, R-23, [[FE-13]], UN 1984

| CASNo_Ref = {{cascite|correct|CAS}}

| EINECS = 200-872-4

| PubChem = 6373

| UNII_Ref = {{fdacite|correct|FDA}}

| InChI = 1/CHF3/c2-1(3)4/h1H

| RTECS = PB6900000

| ChEBI_Ref = {{ebicite|changed|EBI}}

| ChEBI = 24073

}}

|Section2={{Chembox Properties

| C=1|H=1|F=3

| Appearance = Colorless gas

| MeltingPtC = −155.2

| BoilingPtC = −82.1

| Solubility = 1 g/l

| SolubleOther = Soluble

| Solvent = organic solvents

| VaporPressure = 4.38 MPa at 20 °C

| HenryConstant = 0.013 mol·kg⁻¹·bar⁻¹

| pKa = 25–28

| Density = 2.946 kg/m³ (gas, 1 bar, 15 °C)

}}

|Section3={{Chembox Structure

| CrystalStruct =

| Coordination =

| MolShape = [[Tetrahedral]]

}}

|Section7={{Chembox Hazards

| MainHazards = Nervous system depression

| GHSPictograms = {{GHS04}}

| GHSSignalWord = Warning

| HPhrases = {{HPhrases|H280}}

| PPhrases = {{PPhrases|P403}}

| GHS_ref = <ref>GHS: [https://gestis.dguv.de/data?name=038260 GESTIS 038260]</ref>

| NFPA-H = 2

| NFPA-F = 0

| NFPA-R = 0

| NFPA-S =

| FlashPt = Non-flammable

| AutoignitionPt =

}}

|Section9 = {{Chembox Related

|OtherFunction_label = chloromethanes

|OtherCompounds = {{ubl|[[Fluoromethane]] {{chem2|CH3F}}|[[Difluoromethane]] {{chem2|CH2F2}}|[[Tetrafluoromethane]] {{chem2|CF4}}|[[Chloroform]] {{chem2|CHCl3}}|[[Bromoform]] {{chem2|CHBr3}}|[[Iodoform]] {{chem2|CHI3}}|[[Chlorodifluoromethane]] {{chem2|CHF2Cl}}|[[Dichlorofluoromethane]] {{chem2|CHFCl2}}|[[Bromodichloromethane]] {{chem2|CHCl2Br}}|[[Dibromochloromethane]] {{chem2|CHClBr2}}|[[Bromodifluoromethane]] {{chem2|CHF2Br}}|[[Dibromofluoromethane]] {{chem2|CHFBr2}}|[[Deuterated chloroform]] {{chem2|CDCl3}}}}

'''Fluoroform''', or '''trifluoromethane''', is the [[chemical compound]] with the formula {{chem2|CHF3}}. It is a [[hydrofluorocarbon]] as well as being a part of the [[trihalomethane|haloforms]], a class of compounds with the formula {{chem2|CHX3}} (X = [[halogen]]) with C_3v [[symmetry group|symmetry]]. Fluoroform is used in diverse applications in [[organic synthesis]]. It is not an [[ozone depleter]] but is a [[greenhouse gas]].<ref name=SynLett>{{cite journal|journal=Synlett|year=2015|volume=26|issue=13|pages=1911–1912|doi=10.1055/s-0034-1380924|title=Fluoroform (CHF3)|author=ShivaKumar Kyasa|doi-access=free}}</ref>

== Synthesis ==

About 20 million kg per year are produced industrially as both a by-product of and precursor to the manufacture of [[Teflon]].<ref name=SynLett/> It is produced by reaction of [[chloroform]] with [[Hydrogen_fluoride|HF]]:<ref name=Ullmann>{{Ullmann|author=G. Siegemund|author2=W. Schwertfeger|author3=A. Feiring|author4= B. Smart|author5=F. Behr|author6= H. Vogel|author7=B. McKusick|title=Fluorine Compounds, Organic|year=2005|doi=10.1002/14356007.a11_349}}</ref>

:{{chem2|CHCl3 + 3 HF → CHF3 + 3 HCl}}

It is also generated biologically in small amounts apparently by [[decarboxylation]] of [[trifluoroacetic acid]].<ref>Kirschner, E., Chemical and Engineering News 1994, 8.</ref>

===Historical===

Fluoroform was first obtained by [[Maurice Meslans]] in the violent reaction of [[iodoform]] with dry [[silver fluoride]] in 1894.<ref>{{cite journal|title = Recherches sur quelques fluorures organiques de la série grasse|author = Meslans M. M.

|journal = [[Annales de chimie et de physique]]|year = 1894|volume = 7|issue = 1|pages = 346–423|url = http://gallica.bnf.fr/ark:/12148/bpt6k34901c/f344.table}}</ref> The reaction was improved by [[Otto Ruff]] by substitution of silver fluoride by a mixture of [[Mercury(II) fluoride|mercury fluoride]] and [[calcium fluoride]].<ref name="JACS_1937">{{cite journal|title = Fluoroform|author = Henne A. L.|journal = [[Journal of the American Chemical Society]]|year = 1937|volume = 59|issue = 7|pages = 1200–1202|doi = 10.1021/ja01286a012}}</ref> The exchange reaction works with iodoform and [[bromoform]], and the exchange of the first two [[halogen]] atoms by fluorine is vigorous. By changing to a two step process, first forming a [[bromodifluoromethane]] in the reaction of [[antimony trifluoride]] with bromoform and finishing the reaction with mercury fluoride the first efficient synthesis method was found by Henne.<ref name="JACS_1937"/>

== Industrial applications ==

{{chem2|CHF3}} is used in the [[semiconductor]] [[Industry (economics)|industry]] in [[plasma etching]] of [[silicon oxide]] and [[silicon nitride]]. Known as R-23 or HFC-23, it was also a useful [[refrigerant]], sometimes as a replacement for [[chlorotrifluoromethane]] (CFC-13) and is a byproduct of its manufacture.

When used as a fire suppressant, the fluoroform carries the [[DuPont]] trade name, FE-13. {{chem2|CHF3}} is recommended for this application because of its low toxicity, its low reactivity, and its high density. HFC-23 has been used in the past as a replacement for [[Halon 1301]](CFC-13B1) in [[fire suppression system]]s as a total flooding [[gaseous fire suppression]] agent.

=== Organic chemistry ===

Fluoroform is weakly acidic with a pK_''a'' = 25–28 and quite inert. Attempted deprotonation results in defluorination to generate {{chem2|F−}} and [[difluorocarbene]] ({{chem2|CF2}}). Some organocopper and [[organocadmium compound]]s have been developed as trifluoromethylation reagents.<ref>{{Cite journal|last1=Zanardi|first1=Alessandro|last2=Novikov|first2=Maxim A.|last3=Martin|first3=Eddy|last4=Benet-Buchholz|first4=Jordi|last5=Grushin|first5=Vladimir V.|date=2011-12-28|title=Direct Cupration of Fluoroform|journal=Journal of the American Chemical Society|volume=133|issue=51|pages=20901–20913|doi=10.1021/ja2081026|pmid=22136628|issn=0002-7863}}</ref>

Fluoroform is a precursor of the Ruppert-Prakash reagent [[Trifluoromethyltrimethylsilane|{{chem2|CF3Si(CH3)3}}]], which is a source of the nucleophilic {{chem2|CF3−}} anion.<ref>Rozen, S.; Hagooly, A. "Fluoroform" in Encyclopedia of Reagents for Organic Synthesis (Ed: L. Paquette) 2004, J. Wiley & Sons, New York. {{doi| 10.1002/047084289X.rn00522}}</ref><ref>{{Cite journal|last1=Prakash|first1=G. K. Surya|last2=Jog|first2=Parag V.|last3=Batamack|first3=Patrice T. D.|last4=Olah|first4=George A.|date=2012-12-07|title=Taming of Fluoroform: Direct Nucleophilic Trifluoromethylation of Si, B, S, and C Centers|journal=Science|language=en|volume=338|issue=6112|pages=1324–1327|doi=10.1126/science.1227859|issn=0036-8075|pmid=23224551|bibcode=2012Sci...338.1324P|s2cid=206544170}}</ref>

== Greenhouse gas ==

[[File:HFC-23_mm.png|thumb|left|upright=1.2|HFC-23 measured by the Advanced Global Atmospheric Gases Experiment ([http://agage.mit.edu/ AGAGE]) in the lower atmosphere ([[troposphere]]) at stations around the world. Abundances are given as pollution free monthly mean mole fractions in [[Parts-per notation|parts-per-trillion]].]]

[[File:Halogenated gas concentrations 1978-present.png|thumb|left|upright=1.2|Atmospheric concentration of HFC-23 vs. similar man-made gases (right graph), log scale.]]

{{chem2|CHF3}} is a potent [[greenhouse gas]]. A ton of HFC-23 in the atmosphere has the same effect as 11,700 tons of carbon dioxide. This equivalency, also called a 100-yr [[global warming potential]], is slightly larger at 14,800 for HFC-23.<ref name="Forster, P., V. Ramaswamy, P. Artaxo, T. Berntsen, R. Betts, D.W. Fahey, J. Haywood, J. Lean, D.C. Lowe, G. Myhre, J. Nganga, R. Prinn, G. Raga, M. Schulz and R. Van Dorland 2007">{{cite conference|title = Changes in Atmospheric Constituents and in Radiative Forcing.|book-title = Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change|url = http://www.ipcc.ch/pdf/assessment-report/ar4/wg1/ar4-wg1-chapter2.pdf|author = Forster, P.|author2 = V. Ramaswamy|author3 = P. Artaxo|author4 = T. Berntsen|author5 = R. Betts|author6 = D.W. Fahey|author7 = J. Haywood|author8 = J. Lean|author9 = D.C. Lowe|author10 = G. Myhre|author11 = J. Nganga|author12 = R. Prinn|author13 = G. Raga|author14 = M. Schulz|author15 = R. Van Dorland|name-list-style = amp|date = 2007 }}</ref>

The atmospheric lifetime is 270 years.<ref name="Forster, P., V. Ramaswamy, P. Artaxo, T. Berntsen, R. Betts, D.W. Fahey, J. Haywood, J. Lean, D.C. Lowe, G. Myhre, J. Nganga, R. Prinn, G. Raga, M. Schulz and R. Van Dorland 2007"/>

HFC-23 was the most abundant HFC in the global atmosphere until around 2001, when the global mean concentration of [[HFC-134a]] (1,1,1,2-tetrafluoroethane), the chemical now used extensively in automobile air conditioners, surpassed those of HFC-23. Global emissions of HFC-23 have in the past been dominated by the inadvertent production and release during the manufacture of the refrigerant [[HCFC-22]] (chlorodifluoromethane).

Substantial decreases in HFC-23 emissions by developed countries were reported from the 1990s to the 2000s: from 6-8 Gg/yr in the 1990s to 2.8 Gg/yr in 2007.<ref>{{cite journal |doi=10.1029/2009GL041195|title=Recent increases in global HFC-23 emissions|year=2010|last1=Montzka|first1=S. A.|last2=Kuijpers|first2=L.|last3=Battle|first3=M. O.|last4=Aydin|first4=M.|last5=Verhulst|first5=K. R.|last6=Saltzman|first6=E. S.|last7=Fahey|first7=D. W.|journal=Geophysical Research Letters|volume=37|issue=2|pages=n/a|bibcode=2010GeoRL..37.2808M|s2cid=13583576 |url=https://escholarship.org/uc/item/3f31077f}}</ref>

The [[United_Nations_Framework_Convention_on_Climate_Change| UNFCCC]] Clean Development Mechanism [[Clean_Development_Mechanism#Destruction_of_HFC-23| provided funding and facilitated the destruction of HFC-23]].

Developing countries have become the largest producers of HCFC-23 in recent years according to data compiled by the Ozone Secretariat of the World Meteorological Organization.<ref>{{Cite web |url=http://ozone.unep.org/Data_Reporting/Data_Access/ |title=Data Access Centre |access-date=2010-04-03 |archive-url=https://web.archive.org/web/20110721233408/http://ozone.unep.org/Data_Reporting/Data_Access/ |archive-date=2011-07-21 |url-status=dead }}</ref><ref>[https://www.nytimes.com/2012/08/09/world/asia/incentive-to-slow-climate-change-drives-output-of-harmful-gases.html ''Profits on Carbon Credits Drive Output of a Harmful Gas''] August 8, 2012 New York Times</ref><ref>[https://www.nytimes.com/interactive/2012/08/09/world/subsidies-for-a-global-warming-gas.html ''Subsidies for a Global Warming Gas'']</ref> Emissions of all HFCs are included in the UNFCCCs Kyoto Protocol. To mitigate its impact, {{chem2|CHF3}} can be destroyed with electric plasma arc technologies or by high temperature incineration.<ref>{{cite journal|author=Han, Wenfeng|author2=Li, Ying|author3=Tang, Haodong|author4=Liu, Huazhang

|journal=Journal of Fluorine Chemistry|title=Treatment of the potent greenhouse gas, CHF₃. An overview|year=2012|volume=140|page=7–16|doi=10.1016/j.jfluchem.2012.04.012}}</ref>

== Additional physical properties ==

{| class="wikitable"

|-

! Property

! Value

|-

| [[Density]] (ρ) at -100&nbsp;°C (liquid)

| 1.52 g/cm³

|-

| [[Density]] (ρ) at -82.1&nbsp;°C (liquid)

| 1.431 g/cm³

|-

| [[Density]] (ρ) at -82.1&nbsp;°C (gas)

| 4.57&nbsp;kg/m³

|-

| [[Density]] (ρ) at 0&nbsp;°C (gas)

| 2.86&nbsp;kg/m³

|-

| [[Density]] (ρ) at 15&nbsp;°C (gas)

| 2.99&nbsp;kg/m³

|-

| [[Electric dipole moment|Dipole moment]]

| 1.649 D

|-

| [[Critical pressure]] (p_c)

| 4.816 MPa (48.16 bar)

|-

| [[Critical temperature]] (T_c)

| 25.7&nbsp;°C (299 K)

|-

| [[Critical density (thermodynamics)|Critical density]] (ρ_c)

| 7.52&nbsp;mol/l

|-

| [[Compressibility factor]] (Z)

| 0.9913

|-

| [[Acentric factor]] (ω)

| 0.26414

|-

| [[Viscosity]] (η) at 25&nbsp;°C

| 14.4 μPa.s (0.0144 cP)

|-

| [[Specific heat capacity|Molar specific heat]] at constant volume (C_V)

| 51.577 J.mol⁻¹.K⁻¹

|-

| [[Latent heat of vaporization]] (l_b)

| 257.91 kJ.kg⁻¹

|}

== References ==

{{Reflist}}

== Literature ==

*{{cite journal|title = Fluorine Chemistry|author = McBee E. T.|journal = [[Industrial & Engineering Chemistry]]|year = 1947|volume = 39|issue = 3|pages = 236–237|doi = 10.1021/ie50447a002}}

*{{cite journal|title = Growth of fluoroform (CHF₃, HFC-23) in the background atmosphere|author1 = Oram D. E.|author2 = Sturges W. T.|author3 = Penkett S. A.|author4 = McCulloch A.|author5 = Fraser P. J.|journal = [[Geophysical Research Letters]]|year = 1998|volume = 25|issue = 1|pages = 236–237|doi = 10.1029/97GL03483|bibcode = 1998GeoRL..25...35O|doi-access = free}}

*{{cite journal|title = Fluorocarbons in the global environment: a review of the important interactions with atmospheric chemistry and physics|author = McCulloch A.|journal = [[Journal of Fluorine Chemistry]]|year = 2003|volume = 123|issue = 1|pages = 21–29|doi = 10.1016/S0022-1139(03)00105-2}}

== External links ==

* {{ICSC|0577|05}}

* [https://web.archive.org/web/20071011165927/http://ptcl.chem.ox.ac.uk/MSDS/TR/trifluoromethane.html MSDS at Oxford University]

* [https://web.archive.org/web/20061015041042/https://www.mathesontrigas.com/pdfs/msds/MAT09970.pdf MSDS at mathesontrigas.com]

* [http://rsc.org/delivery/_ArticleLinking/DisplayArticleForFree.cfm?doi=a801406j&JournalCode=CC Coupling of fluoroform with aldehydes using an electrogenerated base]

{{Halomethanes}}

{{fluorine compounds}}

[[Category:Fluoroalkanes]]

[[Category:Halomethanes]]

[[Category:Refrigerants]]

[[Category:Fire suppression agents]]

[[Category:Greenhouse gases]]

[[Category:Trifluoromethyl compounds]]

[[Category:Hydrofluorocarbons]]