Lead(II) azide
{{chembox
| Verifiedfields = changed
| Watchedfields = changed
| verifiedrevid = 440042195
| ImageFile = Lead(II)azide.svg
| ImageSize = 200px
| ImageName = Skeletal formula of lead(II) azide
| ImageFile1 = Lead(II)-azide-xtal-a-2x2x2-3D-bs-17.png
| ImageFile2 = Lead azide (modified beta) 01.JPG
| ImageSize2 = 200px
| ImageName2 = Lead(II) azide (modified beta)
| IUPACName = Diazidolead
| OtherNames =
|Section1={{Chembox Identifiers
| CASNo_Ref = {{cascite|correct|??}}
| CASNo = 13424-46-9
| UNII_Ref = {{fdacite|correct|FDA}}
| UNII = 677QUF0Z7P
| UNNumber = 0129
| PubChem = 61600
| SMILES = [N-]=[N+]=N[Pb]N=[N+]=[N-]
| StdInChI = 1S/2N3.Pb/c2*1-3-2;/q2*-1;+2
| StdInChI_Ref = {{stdinchicite|changed|chemspider}}
| InChI = 1S/2N3.Pb/c2*1-3-2;/q2*-1;+2
| InChIKey = ISEQAARZRCDNJH-UHFFFAOYSA-N
| StdInChIKey = ISEQAARZRCDNJH-UHFFFAOYSA-N
| StdInChIKey_Ref = {{stdinchicite|changed|chemspider}}
| EINECS = 236-542-1
| ChemSpiderID_Ref = {{chemspidercite|changed|chemspider}}
| ChemSpiderID = 55508
}}
|Section2={{Chembox Properties
| Formula = {{chem2|Pb(N3)2}}
| Pb=1|N=6
| Appearance = White powder
| Density = 4.71 g/cm3
| MeltingPtC = 190
| MeltingPt_notes = decomposes,{{PubChemLink|61600}} explodes at 350 °C
| BoilingPt =
| Solubility = 2.3 g/100 mL (18 °C)
9.0 g/100 mL (70 °C){{cite book|last = Pradyot|first = Patnaik|year = 2003|title = Handbook of Inorganic Chemicals|publisher = The McGraw-Hill Companies, Inc.|isbn = 0-07-049439-8}}
| SolubleOther = Very soluble in acetic acid
Insoluble in ammonia solution, NH4OH
}}
|Section3={{Chembox Thermochemistry
}}
|Section4={{Chembox Explosive
| ShockSens = High
| FrictionSens = High
| DetonationV = 5180 m/s
| REFactor =
}}
|Section5={{Chembox Hazards
| MainHazards = Harmful, explosive
| GHSPictograms = {{GHS01}}{{GHS06}}{{GHS08}}{{GHS09}}{{cite web|url = http://www.ocsresponds.com/ref/msds/ghs/2014/English/Electric%20Detonators%20Division%201.4.pdf|title = Safety Data Sheet of Electronic Detonators, Division 1.4|date = 2014-03-21|website = ocsresponds.com|publisher = Owen Oil Tools LP|access-date = 2014-06-09}}
| GHSSignalWord = Danger
| HPhrases = {{H-phrases|200|302|332|360|373|410}}
| PPhrases =
| FlashPt =
| AutoignitionPtC = 350
| NFPA-H = 3
| NFPA-F = 0
| NFPA-R = 4
}}
|Section8={{Chembox Related
| OtherAnions =
| OtherCations = Potassium azide
Sodium azide
Copper(II) azide
| OtherFunction =
| OtherFunction_label =
| OtherCompounds = Hydrazoic acid
}}
}}
Lead(II) azide {{chem2|Pb(N3)2}} is an inorganic compound. More so than other azides, it is explosive. It is used in detonators to initiate secondary explosives.{{Greenwood&Earnshaw2nd|page=433}} In a commercially usable form, it is a white to buff powder.
Preparation and handling
Lead(II) azide is prepared by the reaction of sodium azide and lead(II) nitrate in aqueous solution.{{Ullmann|author1=Jacques Boileau |author2=Claude Fauquignon |author3=Bernard Hueber |author4=Hans H. Meyer|title=Explosives|year=2009|doi= 10.1002/14356007.a10_143.pub2}} Lead(II) acetate can also be used.{{cite web|url=http://www.lambdasyn.org/synfiles/bleiazid.htm|title=λ » LambdaSyn – Synthese von Bleiazid|website=www.lambdasyn.org}}{{cite journal | last1 = Verneker | first1 = V. R. Pai | last2 = Forsyth | first2 = Arthur C. | title = Mechanism for controlling the reactivity of lead azide | journal = The Journal of Physical Chemistry | volume = 72 | pages = 111–115 | year = 1968 | doi = 10.1021/j100847a021| url = http://www.dtic.mil/get-tr-doc/pdf?AD=AD0634629 | archive-url = https://web.archive.org/web/20170922143221/http://www.dtic.mil/get-tr-doc/pdf?AD=AD0634629 | url-status = dead | archive-date = September 22, 2017 | url-access = subscription }}
Thickeners such as dextrin or polyvinyl alcohol are often added to the solution to stabilize the precipitated product. In fact, it is normally shipped in a dextrinated solution that lowers its sensitivity.{{cite book |last= Fedoroff |first= Basil T. |author2=Henry A. Aaronson |author3=Earl F. Reese |author4=Oliver E. Sheffield |author5=George D. Clift |title= Encyclopedia of Explosives and Related Items (Vol. 1) |publisher= US Army Research and Development Command TACOM, ARDEC |year= 1960 }}
Production history
Lead azide in its pure form was first prepared by Theodor Curtius in 1891.{{Cite journal| doi = 10.1002/cber.189102402192| issn = 1099-0682| volume = 24| issue = 2| pages = 3341–3349| last = Curtius| first = Th.| title = Neues vom Stickstoffwasserstoff| journal = Berichte der deutschen chemischen Gesellschaft| access-date = 2025-03-26| date = 1891| url = https://onlinelibrary.wiley.com/doi/abs/10.1002/cber.189102402192}} Due to sensitivity and stability concerns, the dextrinated form of lead azide (MIL-L-3055) was developed in the 1920s and 1930s with large scale production by DuPont Co beginning in 1932.{{cite book |title=Energetic Materials, Technology of the Inorganic Azides |volume=2 |publisher=Plenum Press |year=1977 |last1=Fair |first1=Harry David |last2=Walker |first2=Raymond F.}} Detonator development during World War II resulted in the need for a form of lead azide with a more brisant output. RD-1333 lead azide (MIL-DTL-46225), a version of lead azide with sodium carboxymethyl cellulose as a precipitating agent, was developed to meet that need. The Vietnam War saw an accelerated need for lead azide and it was during this time that Special Purpose Lead Azide (MIL-L-14758) was developed; the US government also began stockpiling lead azide in large quantities. After the Vietnam War, the use of lead azide dramatically decreased. Due to the size of the US stockpile, the manufacture of lead azide in the US ceased completely by the early 1990s. In the 2000s, concerns about the age and stability of stockpiled lead azide led the US government to investigate methods to dispose of its stockpiled lead azide and obtain new manufacturers.{{Cite book|last=Lewis|first=T.|title=IEE Seminar on Safety Assurance |chapter=Rolling stock safety assurance [railway safety] |date=2005 |url=http://dx.doi.org/10.1049/ic:20050419 |volume=2005|page=18|publisher=IEE|doi=10.1049/ic:20050419|doi-broken-date=7 December 2024 |isbn=0-86341-574-1}}
Explosive characteristics
Lead azide is highly sensitive and usually handled and stored under water in insulated rubber containers. It will explode after a fall of around 150 mm (6 in) or in the presence of a static discharge of 7 millijoules. Its detonation velocity is around {{convert|5180|m/s|ft/s|abbr=on}}.{{Cite book|last=Thurman, James T.|url=https://www.worldcat.org/oclc/982451395|title=Practical Bomb Scene Investigation, Third Edition.|date=2017|publisher=CRC Press|isbn=978-1-351-85761-1|edition=3rd|location=Milton|oclc=982451395}}
Ammonium acetate and sodium dichromate are used to destroy small quantities of lead azide.{{Cite web|url=http://www.tpub.com/gunners/7.htm|title=Primary (Initiating) Explosives|website=www.tpub.com|access-date=2017-02-13}}
Lead azide has immediate deflagration to detonation transition (DDT), meaning that even small amounts undergo full detonation (after being hit by flame or static electricity).{{cn|date=September 2023}}
Lead azide reacts with copper, zinc, cadmium, or alloys containing these metals to form other azides. For example, copper azide is even more explosive and too sensitive to be used commercially.{{Cite journal|last1=Lazari|first1=Gerasimi|last2=Stamatatos|first2=Theocharis C.|last3=Raptopoulou|first3=Catherine P.|last4=Psycharis|first4=Vassilis|last5=Pissas|first5=Michael|last6=Perlepes|first6=Spyros P.|last7=Boudalis|first7=Athanassios K.|date=2009-04-13|title=A metamagnetic 2D copper(II)-azide complex with 1D ferromagnetism and a hysteretic spin-flop transition|url=https://pubs.rsc.org/en/Content/ArticleLanding/2009/DT/b823423j|journal=Dalton Transactions|language=en|issue=17|pages=3215–3221|doi=10.1039/B823423J|pmid=19421623|issn=1477-9234|url-access=subscription}}
Lead azide was a component of the six .22 (5.6 mm) caliber Devastator rounds fired from a Röhm RG-14 revolver by John Hinckley Jr. in his assassination attempt on U.S. President Ronald Reagan on March 30, 1981. The rounds consisted of lead azide centers with lacquer-sealed aluminum tips designed to explode upon impact. A strong probability exists that the bullet which struck White House press secretary James Brady in the head exploded. The remaining bullets that hit people, including the shot that hit President Reagan, did not explode.{{Cite news|url=https://www.washingtonpost.com/archive/politics/1981/04/04/the-exploding-bullets/e1bef826-a6f5-47e9-bc32-ff3914e1747b/|title=The Exploding Bullets|first1=Pete|last1=Earley|first2=Charles|last2=Babcock|date=April 4, 1981|newspaper=Washington Post}}{{Cite news|last1=Taubman|first1=Philip|last2=Times|first2=Special To the New York|date=1981-04-03|title=Explosive Bullet Struck Reagan, F.b.i. Discovers|language=en-US|work=The New York Times|url=https://www.nytimes.com/1981/04/03/us/explosive-bullet-struck-reagan-fbi-discovers.html|access-date=2020-05-18|issn=0362-4331}}
See also
References
{{reflist}}
External links
{{Commons category|Lead(II) azide}}
- [https://web.archive.org/web/20080111154608/http://www.npi.gov.au/database/substance-info/profiles/50.html National Pollutant Inventory – Lead and Lead Compounds Fact Sheet]
{{Lead compounds}}
{{Azides}}