- Ammonium sulfate
Ammonium sulfate Identifiers CAS number ChemSpider UNII KEGG Jmol-3D images Image 1 Properties Molecular formula (NH4)2SO4 Molar mass 132.14 g/mol Appearance Fine white hygroscopic granules or crystals. Density 1.769 g/cm3 (20 °C) Melting point
235-280 °C, 508-553 K, 455-536 °F (decomposes)
Solubility in water 70.6 g/100 mL (0 °C)
74.4 g/100 mL (20 °C)
103.8 g/100 mL (100 °C)
Solubility insoluble in acetone, alcohol and ether Critical relative humidity 79.2% (30 °C) Hazards EU Index Not listed NFPA 704 Flash point Non-flammable LD50 2840 mg/kg, rat (oral) Related compounds Other anions Ammonium thiosulfate
Other cations Sodium sulfate
Related compounds Ammonium iron(II) sulfate (what is: /?)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Ammonium sulfate (IUPAC-recommended spelling; also ammonium sulphate in British English), (NH4)2SO4, is an inorganic salt with a number of commercial uses. The most common use is as a soil fertilizer. It contains 21% nitrogen as ammonium cations, and 24% sulfur as sulfate anions. In fertilizer the purpose of the sulfate is to reduce the soil pH.
It is used largely as an artificial fertilizer for alkaline soils. In the soil the ammonium ion is released and forms a small amount of acid, lowering the pH balance of the soil , while contributing essential nitrogen for plant growth.
It is also used as an agricultural spray adjuvant for water soluble insecticides, herbicides, and fungicides. There it functions to bind iron and calcium cations that are present in both well water and plant cells. It is particularly effective as an adjuvant for 2,4-D (amine), glyphosate, and glufosinate herbicides.
It is also used in the preparation of other ammonium salts.
In biochemistry, ammonium sulfate precipitation is a common method for purifying proteins by precipitation. As such, ammonium sulfate is also listed as an ingredient for many United States vaccines per the Center for Disease Control.
It has also been used in flame retardant compositions acting much like Diammonium phosphate. As a flame retardant, it lowers the combustion temperature of the material, decreases maximum weight loss rates, and causes an increase in the production of residue or char.
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. In January 2010, these substances were also banned in Afghanistan for the same reason.
- 2 NH3 + H2SO4 → (NH4)2SO4
A mixture of ammonia gas and water vapor is introduced into a reactor that contains a saturated solution of ammonium sulfate and about 2 to 4% of free sulfuric acid at 60 °C. Concentrated sulfuric acid is added to keep the solution acidic, and to retain its level of free acid. The heat of reaction keeps reactor temperature at 60 °C.
Dry, powdered ammonium sulfate may be formed by spraying sulfuric acid into a reaction chamber filled with ammonia gas. The heat of reaction evaporates all water present in the system, forming a powdery salt.
Ammonium sulfate also is manufactured from gypsum (CaSO4·2H2O). Finely divided gypsum is added to an ammonium carbonate solution. Calcium carbonate precipitates out, leaving ammonium sulfate in the solution.
- (NH4)2CO3 + CaSO4 → (NH4)2SO4 + CaCO3
Ammonium sulfate decomposes upon heating above 250°C, firstly forming ammonium bisulfate. Heating at higher temperature result in fully decomposition into ammonia, nitrogen, sulfur dioxide and water. As a salt of a strong acid (i.e. H2SO4) and weak base (i.e. NH3), its solution is acidic; pH of 0.1M solution is 5.5.
Ammonium sulfate forms many double salts (ammonium metal sulfates) when its solution is mixed with equimolar solutions of metal sulfates and the solution is slowly evaporated. Such double metal sulfates include ammonium cobaltous sulfate, ferric ammonium sulfate, ammonium nickel sulfate and ammonium cerous sulfate.
- ^ Handbook of Chemistry and Physics
- ^ Pink Book | Appendix B: Vaccine Excipient & Media Summary, Part 2
- ^ Panera Bread › Menu & Nutrition › Nutrition Information Profile
- ^ Official Subway Restaurants U.S. Products Ingredients Guide
- ^ George, C.W.; Susott, R.A. (April 1971), "Effects of Ammonium Phosphate and Sulfate on the Pyrolysis and Combustion of Cellulose", Research Paper INT-90 (Intermountain Forest and Range Experiment Station: USDA Forest Service), http://openlibrary.org/b/OL16022833M/Effects_of_ammonium_phosphate_and_sulfate_on_the_pyrolysis_and_combustion_of_cellulose
- ^ a b Pradyot Patnaik. Handbook of Inorganic Chemicals. McGraw-Hill, 2002, ISBN 0-07-049439-8
- ^ http://www.mindat.org/min-2584.html/ Mindat data
- ^ LIU Ke-wei, CHEN Tian-lang, Studies on the thermal decomposition of ammonium sulfate, Chemical Research and Application, vol. 14, no. 6 (2002)
- Properties: UNIDO and International Fertilizer Development Center (1998), Fertilizer Manual, Kluwer Academic Publishers, ISBN 0-7923-5032-4.
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Look at other dictionaries:
ammonium sulfate — n. an ammonium salt, (NH4) 2SO4, made chiefly from synthetic ammonia and used in making fertilizers, in treating water, etc … English World dictionary
ammonium sulfate — n a colorless crystalline salt (NH4)2SO4 used as a fertilizer and in medicine as a local analgesic … Medical dictionary
ammonium sulfate — amonio sulfatas statusas T sritis chemija formulė (NH₄)₂SO₄ atitikmenys: angl. ammonium sulfate rus. аммоний сернокислый; аммония сульфат ryšiai: sinonimas – diamonio tetraoksosulfatas … Chemijos terminų aiškinamasis žodynas
ammonium sulfate — noun : a colorless crystalline salt (NH4)2SO4 occurring in nature as mascagnite and made usually by reaction of sulfuric acid with ammonia and used chiefly as a fertilizer * * * Chem. a white, crystalline, water soluble solid, (NH4)2SO4, used… … Useful english dictionary
ammonium sulfate — noun Date: 1869 a colorless crystalline salt (NH4)2SO4 used chiefly as a fertilizer … New Collegiate Dictionary
ammonium sulfate — Chem. a white, crystalline, water soluble solid, (NH4)2SO4, used chiefly as a fertilizer. [1800 85] * * * … Universalium
ammonium sulfate — noun An inorganic chemical compound, (NH)SO, commonly used as a fertilizer and as a food additive (E517) used as an improving agent … Wiktionary
ammonium sulfate — ammo′nium sul′fate n. chem. a white, crystalline, water soluble solid, (NH4)2SO4, used chiefly as a fertilizer • Etymology: 1800–85 … From formal English to slang
Ammonium sulfate precipitation — is a method of protein purification by altering solubility of protein. It is a specific case of a more general technique known as salting out.Ammonium sulfate is commonly used as its solubility is so high that salt solutions with high ionic… … Wikipedia
aluminium-ammonium sulfate — aliuminio amonio alūnas statusas T sritis chemija formulė NH₄Al(SO₄)₂·12H₂O atitikmenys: angl. aluminium ammonium alum; aluminium ammonium disulfate; aluminium ammonium sulfate; ammonium alum rus. алюминиево аммониевые квасцы ryšiai: sinonimas –… … Chemijos terminų aiškinamasis žodynas