- Sulfamic acid
Name = Sulfamic acid
ImageFile = Sulfamic.png
ImageName = Sulfamic acid
IUPACName = Sulfamic acid
Section1 = Chembox Identifiers
CASNo = 5329-14-6
SMILES = H2-N-SO3-H
Section2 = Chembox Properties
Formula = H3NSO3
MolarMass = 97.10 g/mol
MeltingPt = 205 °C (401 °F)
BoilingPt = Decomposes
Density = 2.15 g/cm3
pKa = 1.18 (1% solution @25 °C (77 °F)
Solvent = other solvents
SolubleOther = Soluble
Sulfamic acid, also known as amidosulfonic acid, amidosulfuric acid, aminosulfonic acid, and sulfamidic acid, is a molecular compound with the formula H3NSO3. This colorless, water-soluble compound finds many applications.
Sulfamic acid (H3NSO3) may be considered an intermediate compound between
sulfuric acid(H2SO4), and sulfamide(H4N2SO2), effectively - though see below - replacing an -OH group with an -NH2 group at each step. This pattern can extend no further in either direction without breaking down the -SO2 group.
tructure and reactivity
First, it should be noticed that the compound is well described by the formula H3NSO3, not the
tautomerH2NSO2(OH). The relevant bond distances are S=O, 1.44 and S-N 1.77 Å. The greater length of the S-N distance is consistent with a single bond. [J. W. Bats, P. Coppens, T. F. Koetzle " [http://dx.doi.org/10.1107/S0567740877002568 The Experimental Charge Density in Sulfur-Containing Molecules: A Study of the Deformation Electron Density in Sulfamic Acid at 78 K by X-ray and Neutron Diffraction] " "Acta Crystallographica" 1977, "B33", pages 37–45.] Furthermore, a neutron diffractionstudy located the hydrogen atoms, all three of which are 1.03 Å distant from nitrogen cite journal | author = R. L. Sass | year = 1960 | title = A neutron diffraction study on the crystal structure of sulfamic acid | journal = Acta Cryst. | volume = 13 | issue = 4 | month = April | pages = 320-324 | doi = 10.1107/S0365110X60000789 ] . The structures shown with this article are for the two main tautomers.
Sulfamic acid is a weak acid, "K"a = 1.01 x 10−1. Because the solid is non-
hygroscopic, it is used as a standard in acidometry(quantitative assays of acid content). Double deprotonation can be effected in NH3 solution to give [HNSO3] 2−.:
Sulfamic acid melts at 205 °C before decomposing at higher temperatures to H2O, SO3, SO2, and N2.
Water solutions are unstable and slowly hydrolyze to
ammonium bisulfate, but the crystalline solid is indefinitely stable under ordinary storage conditions.
The behavior of H3NSO3 resembles that of
urea, (H2N)2CO, in some ways. Both feature amino groups linked to electron-withdrawing centers that can participate in delocalized bonding. Both liberate ammoniaupon heating in water.
The most famous application of sulfamic acid is in the synthesis of compounds that taste sweet. Reaction with
cyclohexylaminefollowed by addition of NaOH gives C6H11NHSO3Na, sodium cyclamate. Related compounds are also sweeteners, see acesulfame potassium. Sulfamates (O-substituted-, N-substituted-, or di-/tri-substituted derivatives of sulfamic acid) have been used in the design of many types of therapeutic agents such as antibiotics, nucleoside/nucleotide human immunodeficiency virus(HIV) reverse transcriptase inhibitors, HIV protease inhibitors (PIs), anti-cancer drugs ( steroid sulfataseand carbonic anhydraseinhibitors), anti-epileptic drugs, and weight loss drugs.
Sulfamic acid is used as an acidic
cleaningagent, typically for metals and ceramics. It is a replacement for hydrochloric acidfor the removal of rust. In households, it is often found as a descaling agentin detergents used for removal of limescale. From all acid, Sulfamic acid has the best water descaling property, thus also its application in cleaning dairy farm equipment and beer brewery. Although it is considered less corrosive than hydrochloric acid, in its application as acid cleaning, it is very common to find user adding corrosion inhibitor.
Sulfamic acid is used in the S.C. Johnson & Sons, Inc. "Scrubbing Bubbles Fizz-Its Toilet Tablets."
*Ingredient in Denture Tablets
*Ingredient in fire extinguishing media. Sulfamic acid is the main raw material for
Ammonium_sulfamatewhich is a widely used herbicide and fire retardant material for household product.
*Pulp and paper industry as a chloride stabilizer
nitrous oxideby reaction with nitric acid
*Sulfamates and their therapeutic potential. Med Res Rev. 2005 Mar;25(2):186-228. Review.
*R. J. Cremlyn “An Introduction to Organosulfur Chemistry” John Wiley and Sons: Chichester (1996). ISBN 0-471-95512-4
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Look at other dictionaries:
sulfamic acid — |səl|famik noun Etymology: International Scientific Vocabulary sulf + amide + ic 1. : a strong crystalline acid H2NSO3H made usually by reaction of sulfuric acid, sulfur trioxide, and urea and used chiefly as a weed killer, in cleaning metals,… … Useful english dictionary
sulfamic acid — sulfamo rūgštis statusas T sritis chemija formulė H₂NSO₃H atitikmenys: angl. sulfamic acid rus. сульфаминовая кислота … Chemijos terminų aiškinamasis žodynas
sulfamic acid — sul·fam·ic acid or chiefly Brit sul·pham·ic acid səl .fam ik n a strong crystalline acid H3NSO3 made usu. by reaction of sulfuric acid, sulfur trioxide, and urea … Medical dictionary
sulfamic acid — noun the compound HNS(=O)OH and its N hydrocarbyl derivatives Syn: sulfamidic acid … Wiktionary
sulfamic — adjective Of or pertaining to sulfamic acid or its derivatives … Wiktionary
cyclohexylsulfamic acid — /suy kleuh hek seuhl sul fam ik, sik leuh /, Chem. See cyclamic acid. [CYCLO + HEXYL + sulfamic acid (appar. (chloro)sulf(onic) + AM(MONIA) + IC)] * * * … Universalium
sulphamic acid — [sʌl famɪk] (US sulfamic acid) noun Chemistry a crystalline acid used in cleaning agents. Origin C19: from sulphur + amide + ic … English new terms dictionary
sulphamic acid — /sʌlˌfæmɪk ˈæsəd/ (say sul.famik asuhd) noun a white crystalline solid, HSO3NH2, which gives weakly acid water solutions; used as a metal and ceramic cleaner and as a stabilising agent for chlorine and hypochlorite in swimming pools, etc. Also,… … Australian English dictionary
cyclohexylsulfamic acid — /suy kleuh hek seuhl sul fam ik, sik leuh /, Chem. See cyclamic acid. [CYCLO + HEXYL + sulfamic acid (appar. (chloro)sulf(onic) + AM(MONIA) + IC)] … Useful english dictionary
sulfamidic acid — noun sulfamic acid … Wiktionary