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

{{Short description|1=Organic compound (H2C=C=CH2)}}

| Verifiedimages = changed

| Watchedfields = changed

| verifiedrevid = 464215747

| ImageFileL1 = Propadiene structure.svg

| ImageFileL1_Ref = {{chemboximage|correct|??}}

| ImageNameL1 = Stereo structural formula of propadiene with explicit hydrogens

| ImageFileR1_Ref = {{Chemboximage|correct|??}}

| ImageNameR1 = Spacefill model of propadiene

| ImageFile2_Ref = {{Chemboximage|correct|??}}

| ImageSize2 = 160

| ImageName2 = Ball and stick model of propadiene

| PIN = Propadiene<ref name=iupac2013>{{cite book | title = Nomenclature of Organic Chemistry : IUPAC Recommendations and Preferred Names 2013 (Blue Book) | publisher = [[Royal Society of Chemistry|The Royal Society of Chemistry]] | date = 2014 | location = Cambridge | page = 375 | doi = 10.1039/9781849733069-FP001 | isbn = 978-0-85404-182-4 | quote = The name allene, for {{chem2|CH2\dC\dCH2}}, is retained for general nomenclature only; substitution is allowed, but not by alkyl or any other group that extends the carbon chain, nor characteristic groups expressed by suffixes. The systematic name, propadiene, is the preferred IUPAC name.}}</ref>

| OtherNames = Allene<ref name=iupac2013 /><br />Propadiene

|Section1={{Chembox Identifiers

| CASNo = 463-49-0

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

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

| UNII = 4AV0LZ8QKB

| PubChem = 10037

| ChemSpiderID = 9642

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

| EINECS = 207-335-3

| UNNumber = 2200

| MeSHName = Propadiene

| ChEBI_Ref = {{ebicite|correct|EBI}}

| ChEMBL = 116960

| ChEMBL_Ref = {{ebicite|correct|EBI}}

| Beilstein = 1730774

| Gmelin = 860

| SMILES = C=C=C

| SMILES1 = C(=C)=C

| StdInChI = 1S/C3H4/c1-3-2/h1-2H2

| StdInChI_Ref = {{stdinchicite|correct|chemspider}}

| StdInChIKey = IYABWNGZIDDRAK-UHFFFAOYSA-N

| StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}

|Section2={{Chembox Properties

| C=3 | H=4

| Appearance = Colorless gas

| MeltingPtC = -136

| BoilingPtC = -34

| LogP = 1.45}}

|Section3={{Chembox Hazards

| ExternalSDS = [http://encyclopedia.airliquide.com/Encyclopedia.asp?GasID=52 External MSDS]

| GHSPictograms = {{GHS flame}} {{GHS gas cylinder}}<ref name="GESTIS">{{GESTIS|ZVG=13750 |CAS=463-49-0 |Name=Allene |Date=17 November 2020}}</ref>

| GHSSignalWord = Danger

| HPhrases = {{H-phrases|220|280}}<ref name=GESTIS/>

| PPhrases = {{P-phrases|210|377|381|410+403}}<ref name=GESTIS/>

| NFPA-H = 0

| NFPA-F = 4

| NFPA-R = 3

| ExploLimits = 13%}}

'''Propadiene''' ({{IPAc-en|p|r|oʊ|p|ə|ˈ|d|aɪ|iː|n}}) or '''allene''' ({{IPAc-en|ˈ|æ|l|iː|n}}) is the [[organic compound]] with the formula {{chem2|H2C\dC\dCH2}}. It is the simplest [[allene]], i.e. a compound with two adjacent carbon [[double bond]]s.<ref>{{GoldBookRef | title = allenes | file = A00238}}</ref> As a constituent of [[MAPP gas]], it has been used as a fuel for specialized [[welding]].

==Production and equilibrium with methylacetylene==

Allene exists in equilibrium with [[methylacetylene]] (propyne) and the mixture is sometimes called MAPD for ''m''ethyl''a''cetylene-''p''ropa''d''iene:

:{{chem2 | H3CC\tCH <-> H2C\dC\dCH2 }}

for which {{nowrap|1=''K''{{sub|eq}} = 0.22}} at 270&nbsp;°C or 0.1 at 5&nbsp;°C.

MAPD is produced as a side product, often an undesirable one, of [[dehydrogenation]] of [[propane]] to produce [[propene]], an important [[feedstock]] in the [[chemical industry]]. MAPD interferes with the [[Ziegler–Natta catalyst|catalytic]] [[polymerization]] of propene.<ref>Klaus Buckl, Andreas Meiswinkel "Propyne" in ''Ullmann's Encyclopedia of Industrial Chemistry'', 2008, Wiley-VCH, Weinheim. {{doi|10.1002/14356007.m22_m01}}</ref>

==References==

{{Reflist}}

{{Hydrocarbons}}

{{Authority control}}

[[Category:Fuel gas]]

[[Category:Alkadienes]]