Ammonium nitrate - wikipedia Ammonium nitrate Ammonium nitrate Names IUPAC name Ammonium nitrate Identifiers CAS Number 6484 - 52 - 2 3D model ( JSmol ) Interactive image ChemSpider 21511 ECHA InfoCard 100.026. 680 EC Number 229 - 347 - 8 PubChem CID 22985 RTECS number BR9050000 UNII T8YA51M7Y6 UN number 0222 -- with > 0.2 % combustible substances 1942 -- with < = 0.2 % combustible substances 2067 -- fertilizers 2426 -- liquid InChI InChI = 1S / NO3. H3N / c2 - 1 ( 3 ) 4 ; / h ; 1H3 / q - 1 ; / p + 1 Key : DVARTQFDIMZBAA - UHFFFAOYSA - O InChI = 1 / NO3. H3N / c2 - 1 ( 3 ) 4 ; / h ; 1H3 / q - 1 ; / p + 1 Key : DVARTQFDIMZBAA - IKLDFBCSAH SMILES ( O - ) ( N+ ) ( ( O - ) ) = O. ( NH4+ ) Properties Chemical formula NH NO Molar mass 80.043 g / mol Appearance white / grey solid Density 1.725 g / cm ( 20 ° C ) Melting point 169.6 ° C ( 337.3 ° F ; 442.8 K ) Boiling point approx. 210 ° C ; decomposes Solubility in water Endothermic 118 g / 100 ml ( 0 ° C ) 150 g / 100 ml ( 20 ° C ) 297 g / 100 ml ( 40 ° C ) 410 g / 100 ml ( 60 ° C ) 576 g / 100 ml ( 80 ° C ) 1024 g / 100 ml ( 100 ° C ) Magnetic susceptibility ( χ ) - 33.6 10 cm / mol Structure Crystal structure trigonal Explosive data Shock sensitivity very low Friction sensitivity very low Detonation velocity 5270 m / s Hazards Main hazards Explosive, Oxidizer GHS pictograms GHS signal word Warning GHS hazard statements H201, H271, H319 GHS precautionary statements P220, P221, P271, P280, P264, P372 NFPA 704 0 OX Lethal dose or concentration ( LD, LC ) : LD ( median dose ) 2085 -- 5300 mg / kg ( oral in rats, mice ) Related compounds Other anions Ammonium nitrite Other cations Sodium nitrate Potassium nitrate Hydroxylammonium nitrate Related compounds Ammonium perchlorate Except where otherwise noted, data are given for materials in their standard state ( at 25 ° C ( 77 ° F ), 100 kPa ). Y verify ( what is ? ) Infobox references Ammonium nitrate is a chemical compound, the nitrate salt of the ammonium cation. It has the chemical formula N H N O, simplified to N H O. It is a white crystal solid and is highly soluble in water. It is predominantly used in agriculture as a high - nitrogen fertilizer. Its other major use is as a component of explosive mixtures used in mining, quarrying, and civil construction. It is the major constituent of ANFO, a popular industrial explosive which accounts for 80 % of explosives used in North America ; similar formulations have been used in improvised explosive devices. Many countries are phasing out its use in consumer applications due to concerns over its potential for misuse. Contents 1 Occurrence 2 Production 2.1 Reactions 2.2 Crystalline phases 3 Applications 3.1 Fertilizer 3.2 Explosives 3.2. 1 Mixture with fuel oil 3.2. 2 Terrorism 3.3 Niche uses 4 Safety, handling, and storage 5 Health hazards 6 Disasters 7 References 8 External links Occurrence Ammonium nitrate is found as a natural mineral ( gwihabaite -- the ammonium analogue of saltpetre, which is correctly called niter, and other nitre minerals such as sodium nitrate known as nitratine ) in the driest regions of the Atacama Desert in Chile, often as a crust on the ground and / or in conjunction with other nitrate, iodate, and halide minerals. Ammonium nitrate was mined there in the past, but virtually 100 % of the chemical now used is synthetic. Production The industrial production of ammonium nitrate entails the acid - base reaction of ammonia with nitric acid : HNO + NH → NH NO Ammonia is used in its anhydrous form ( i.e., gas form ) and the nitric acid is concentrated. This reaction is violent owing to its highly exothermic nature. After the solution is formed, typically at about 83 % concentration, the excess water is evaporated to an ammonium nitrate ( AN ) content of 95 % to 99.9 % concentration ( AN melt ), depending on grade. The AN melt is then made into `` prills '' or small beads in a spray tower, or into granules by spraying and tumbling in a rotating drum. The prills or granules may be further dried, cooled, and then coated to prevent caking. These prills or granules are the typical AN products in commerce. The ammonia required for this process is obtained by the Haber process from nitrogen and hydrogen. Ammonia produced by the Haber process is oxidized to nitric acid by the Ostwald process. Another production method is a variant of the Odda process : Ca ( NO ) + 2 NH + CO + H O → 2 NH NO + CaCO The products, calcium carbonate and ammonium nitrate, may be separately purified or sold combined as calcium ammonium nitrate. Ammonium nitrate can also be made via metathesis reactions : ( NH ) SO + Ba ( NO ) → 2 NH NO + BaSO NH Cl + AgNO → NH NO + AgCl Reactions Ammonium nitrate reacts with metal hydroxides, releasing ammonia and forming alkali metal nitrate : NH NO + MOH → NH + H O + MNO ( M = Na, K ) Ammonium nitrate leaves no residue when heated : NH NO → N O + 2H O When rapidly heated or exploded the predominant reaction is : 2NH NO → 2N + O + 4H O Ammonium nitrate is also formed in the atmosphere from emissions of NO, SO, and NH, and is a secondary component of some PM particulates. Crystalline phases Transformations of the crystal states due to changing conditions ( temperature, pressure ) affect the physical properties of ammonium nitrate. These crystalline states have been identified : System Temperature ( ° C ) State Volume change ( % ) > 169.6 liquid 169.6 to 125.2 cubic − 2.1 II 125.2 to 84.2 tetragonal + 1.3 III 84.2 to 32.3 α - rhombic − 3.6 IV 32.3 to − 16.8 β - rhombic + 2.9 V < − 16.8 tetragonal The type V crystal is a quasi cubic form related to caesium chloride, the nitrogen atoms of the nitrate anions and the ammonium cations are at the sites in a cubic array where Cs and Cl would be in the CsCl lattice. Applications Fertilizer Ammonium nitrate is an important fertilizer with the NPK rating 34 - 0 - 0 ( 34 % nitrogen ). It is less concentrated than urea ( 46 - 0 - 0 ), giving ammonium nitrate a slight transportation disadvantage. Ammonium nitrate 's advantage over urea is that it is more stable and does not rapidly lose nitrogen to the atmosphere. Explosives Ammonium nitrate is not, on its own, an explosive, but it readily forms explosive mixtures with varying properties when combined with primary explosives such as azides or with fuels such as aluminum powder or fuel oil. Mixture with fuel oil Main article : ANFO ANFO is a mixture of 94 % ammonium nitrate ( `` AN '' ) and 6 % fuel oil ( `` FO '' ) widely used as a bulk industrial explosive. It is used in coal mining, quarrying, metal mining, and civil construction in undemanding applications where the advantages of ANFO 's low cost and ease of use matter more than the benefits offered by conventional industrial explosives, such as water resistance, oxygen balance, high detonation velocity, and performance in small diameters. Terrorism Ammonium nitrate - based explosives were used in the Sterling Hall bombing in Madison, Wisconsin, 1970, the Oklahoma City bombing in 1995, the 2011 Delhi bombings, the 2013 Hyderabad blasts, and the 2011 bombing in Oslo. In November 2009, a ban on ammonium sulfate, ammonium nitrate, and calcium ammonium nitrate fertilizers was imposed in the former Malakand Division -- comprising the Upper Dir, Lower Dir, Swat, Chitral, and Malakand districts of the North West Frontier Province ( NWFP ) of Pakistan -- by the NWFP government, following reports that those chemicals were used by militants to make explosives. Due to these bans, `` Potassium chlorate -- the stuff that makes matches catch fire -- has surpassed fertilizer as the explosive of choice for insurgents. '' Niche uses Ammonium nitrate is used in some instant cold packs, as its dissolution in water is highly endothermic. It also was used, in combination with independently explosive `` fuels '' such as guanidine nitrate, as a cheaper ( but less stable ) alternative to 5 - aminotetrazole in the inflators of airbags manufactured by Takata Corporation, which were recalled as unsafe after killing 14 people. Safety, handling, and storage Health and safety data are shown on the safety data sheets available from suppliers and found on the internet. In response to several explosions resulting in the deaths of numerous people, U.S. agencies of Environmental Protection ( EPA ), Occupational Health and Safety ( OSHA ) and the Bureau of Alcohol, Tobacco and Firearms jointly issued safety guidelines. Heating or any ignition source may cause violent combustion or explosion. Ammonium nitrate reacts with combustible and reducing materials as it is a strong oxidant. Although it is mainly used for fertilizer, it can be used for explosives. It was sometimes used to blast away earth to make farm ponds. Ammonium nitrate is also used to modify the detonation rate of other explosives, such as trinitrotoluene in the form of amatol. Numerous safety guidelines are available for storing and handling ammonium nitrate. It should not be stored near combustible substances. Ammonium nitrate is incompatible with certain substances such as chlorates, mineral acids and metal sulfides, contact with which can lead to vigorous or even violent decomposition. Ammonium nitrate has a critical relative humidity of 59.4 %, above which it will absorb moisture from the atmosphere. Therefore, it is important to store ammonium nitrate in a tightly sealed container. Otherwise, it can coalesce into a large, solid mass. Ammonium nitrate can absorb enough moisture to liquefy. Blending ammonium nitrate with certain other fertilizers can lower the critical relative humidity. The potential for use of the material as an explosive has prompted regulatory measures. For example, in Australia, the Dangerous Goods Regulations came into effect in August 2005 to enforce licensing in dealing with such substances. Licenses are granted only to applicants ( industry ) with appropriate security measures in place to prevent any misuse. Additional uses such as education and research purposes may also be considered, but individual use will not. Employees of those with licenses to deal with the substance are still required to be supervised by authorized personnel and are required to pass a security and national police check before a license may be granted. Health hazards Health and safety data are shown on the material safety data sheets, which are available from suppliers and can be found on the internet. Ammonium nitrate is not hazardous to health and is usually used in fertilizer products. Ammonium nitrate has an LD of 2217 mg / kg, which for comparison is about two - thirds that of table salt. Disasters Main article : Ammonium nitrate disasters Ammonium nitrate decomposes into the gases nitrous oxide and water vapor when heated ( not an explosive reaction ) ; however, it can be induced to decompose explosively by detonation. Large stockpiles of the material can be a major fire risk due to their supporting oxidation, and may also detonate, as happened in the Texas City disaster of 1947, which led to major changes in the regulations for storage and handling. Two major classes of incidents resulting in explosions are : The explosion happens by the mechanism of shock - to - detonation transition. The initiation happens by an explosive charge going off in the mass, by the detonation of a shell thrown into the mass, or by detonation of an explosive mixture in contact with the mass. The examples are Kriewald, Morgan ( present - day Sayreville, New Jersey ), Oppau, and Tessenderlo. The explosion results from a fire that spreads into the ammonium nitrate itself ( Texas City, Brest, Oakdale PA ), or from a mixture of ammonium nitrate with a combustible material during the fire ( Repauno, Cherokee, Nadadores ). The fire must be confined at least to a degree for successful transition from a fire to an explosion ( a phenomenon known as `` deflagration - to - detonation transition '' ). Pure, compact AN is stable and very difficult to ignite, and numerous cases exist when even impure AN did not explode in a fire. References Jump up ^ Pradyot Patnaik. Handbook of Inorganic Chemicals. McGraw - Hill, 2002, ISBN 0 - 07 - 049439 - 8 Jump up ^ Martel, B. ; Cassidy, K. ( 2004 ). Chemical Risk Analysis : A Practical Handbook. Butterworth -- Heinemann. p. 362. ISBN 1 - 903996 - 65 - 1. Jump up ^ `` Archived copy ''. Archived from the original on 2015 - 02 - 17. Retrieved 2015 - 03 - 13. Jump up ^ Karl - Heinz Zapp `` Ammonium Compounds '' in Ullmann 's Encyclopedia of Industrial Chemistry 2012, Wiley - VCH, Weinheim. doi : 10.1002 / 14356007. a02_243 Jump up ^ Ammonium nitrate sold by ton as U.S. regulation is stymied. - The Dallas Morning News Jump up ^ http://www.google.com/patents/pdf/Process_of_producing_concentrated_soluti.pdf?id=XronAAAAEBAJ&output=pdf&sig=ACfU3U0iYFRDUxltKLaVind-3wwP_JYPxg Jump up ^ Int Panis, LLR ( 2008 ). `` The Effect of Changing Background Emissions on External Cost Estimates for Secondary Particulates '' ( PDF ). Open Environmental Sciences. 2 : 47 -- 53. doi : 10.2174 / 1876325100802010047. Jump up ^ Choi, C.S. ; Prask, H.J. ( 1983 ). `` The structure of ND NO phase V by neutron powder diffraction ''. Acta Crystallographica B. 39 ( 4 ) : 414 -- 420. doi : 10.1107 / S0108768183002669. Jump up ^ Nutrient Content of Fertilizer Materials Jump up ^ Manhattan Bombs Provide Trove of Clues - The New York Times ^ Jump up to : Cook, Melvin A. ( 1974 ). The Science of Industrial Explosives. IRECO Chemicals. p. 1. ASIN B0000EGDJT. Jump up ^ Potassium chlorate -- the stuff that makes matches catch fire -- has surpassed fertilizer as the explosive of choice for insurgents. Jump up ^ US 5531941 Jump up ^ Airbag Compound Has Vexed Takata for Years - The New York Times Jump up ^ A Cheaper Airbag, and Takata 's Road to a Deadly Crisis. - The New York Times Jump up ^ Ammonium nitrate MSDS Jump up ^ Chemical Advisory : Safe Storage, Handling, and Management of Ammonium Nitrate United States Environmental Protection Agency Jump up ^ Pradyot Patnaik ( 2002 ). Handbook of Inorganic Chemicals. McGraw - Hill. ISBN 0 - 07 - 049439 - 8. Jump up ^ Pothole pond Jump up ^ Progressive Farmer Magazine Jump up ^ Storing and handling ammonium nitrate Jump up ^ Chemical Engineering Transactions Archived 2016 - 04 - 14 at the Wayback Machine. Jump up ^ Fertilizers Europe ( 2006 ). `` Guidance for Compatibility of Fertilizer Blending Materials '' ( PDF ). Jump up ^ Dangerous Goods ( HCDG ) Regulations Jump up ^ Ammonium Nitrate - Regulating its use, Balancing Access & Protection from `` Worksafe Victoria ''. Archived from the original on 2011 - 03 - 11. ^ Jump up to : CF Industries. `` Ammonium nitrate MSDS '' ( PDF ). Archived from the original ( PDF ) on 2014 - 03 - 27. Jump up ^ `` Chemicalland21 -- Ammonium Nitrate ''. Archived from the original on 2012 - 01 - 10. Jump up ^ `` Ammonium Nitrate ''. Paton Fertilizers Pty Ltd. 2005. Jump up ^ `` Material Safety Data Sheet, Ammonium nitrate MSDS ''. Properties : UNIDO and International Fertilizer Development Center ( 1998 ), Fertilizer Manual, Kluwer Academic Publishers, ISBN 0 - 7923 - 5032 - 4. External links International Chemical Safety Card 0216 `` Storing and Handling Ammonium Nitrate '', United Kingdom Health and Safety Executive publication INDG230 ( 1986 ) Chemical Advisory : Safe Storage, Handling, and Management of Ammonium Nitrate United States Environmental Protection Agency Calculators : surface tensions, and densities, molarities and molalities of aqueous ammonium nitrate Salts and covalent derivatives of the Nitrate ion HNO He LiNO Be ( NO ) B ( NO ) NO, NH NO O FNO Ne NaNO Mg ( NO ) Al ( NO ) Si ClONO Ar KNO Ca ( NO ) Sc ( NO ) Ti ( NO ) VO ( NO ) Cr ( NO ) Mn ( NO ) Fe ( NO ), Fe ( NO ) Co ( NO ), Co ( NO ) Ni ( NO ) Cu ( NO ) Zn ( NO ) Ga ( NO ) Ge As Se Br Kr RbNO Sr ( NO ) Y Zr ( NO ) Nb Mo Tc Ru Rh Pd ( NO ) AgNO Cd ( NO ) In Sn Sb ( NO ) Te Xe ( NO ) CsNO Ba ( NO ) Hf Ta Re Os Ir Pt Au Hg ( NO ), Hg ( NO ) Tl ( NO ), TlNO Pb ( NO ) Bi ( NO ) BiO ( NO ) Po At Rn FrNO Ra ( NO ) Rf Db Sg Bh Hs Mt Ds Rg Cn Nh Fl Mc Lv Ts Og ↓ La ( NO ) Ce ( NO ), Ce ( NO ) Pr Nd Pm Sm Eu ( NO ) Gd ( NO ) Tb Dy Ho Er Tm Yb Lu Ac ( NO ) Th ( NO ) Pa UO ( NO ) Np Pu Am Cm Bk Cf Es Fm Md No Lr NDL : 00576059 Retrieved from `` https://en.wikipedia.org/w/index.php?title=Ammonium_nitrate&oldid=854406125 '' Categories : Ammonium compounds Nitrates Explosive chemicals Rocket oxidizers Pyrotechnic oxidizers Nitrogen cycle Soil improvers Inorganic fertilizers Oxidizing agents Hidden categories : All articles with dead external links Articles with dead external links from July 2017 Articles with permanently dead external links Webarchive template wayback links Articles without EBI source Articles without KEGG source ECHA InfoCard ID from Wikidata Chembox having GHS data Articles containing unverified chemical infoboxes Wikipedia articles with NDL identifiers Talk Contents About Wikipedia Afrikaans Asturianu تۆرکجه Български Català Čeština Dansk Deutsch Español Esperanto فارسی Français 한국어 Հայերեն हिन्दी Hrvatski Bahasa Indonesia Íslenska Italiano עברית Қазақша Kurdî Latviešu Lietuvių Magyar Македонски मराठी Монгол Nederlands 日本 語 Norsk Oʻzbekcha / ўзбекча پښتو Polski Português Română Русский Scots Simple English سنڌي Slovenčina Slovenščina Српски / srpski Srpskohrvatski / српскохрватски Suomi Svenska தமிழ் తెలుగు Türkçe Українська Tiếng Việt Winaray 中文 45 more Edit links This page was last edited on 11 August 2018, at 03 : 32 ( UTC ). 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Question: what happens when ammonium nitrate reacts with water
Answer: endothermic