IUPAC nomenclature of inorganic chemistry 3148933 220922910 2008-06-22T06:25:01Z Blindman shady 1340584 /* Naming acids */ The '''IUPAC nomenclature of inorganic chemistry''' is a [[systematic name|systematic]] method of naming [[inorganic]] [[chemical compound]]s as recommended by the [[International Union of Pure and Applied Chemistry]] (IUPAC). Ideally, every [[inorganic compound]] should have a name from which an unambiguous [[Chemical formula|formula]] can be determined. There is also an [[IUPAC nomenclature of organic chemistry]]. The names "[[caffeine]]" and "3,7-dihydro-1,3,7-trimethyl-1H-purine-2,6-dione" both describe the same chemical. The systematic name encodes the structure and composition of the caffeine molecule in some detail, and provides an unambiguous reference to this compound, whereas the name "caffeine" just names it. These advantages make the systematic name far superior to the common name when absolute clarity and precision are required. However, even professional chemists will use the non-systematic name almost all of the time, because caffeine is a well-known common chemical with a unique structure. Similarly, H<sub>2</sub>O is most often simply called [[water]] in English, though other chemical names do exist. # Single atom anions are named with an ''-ide'' suffix: for example, H<sup>−</sup> is hydride. # Compounds with a positive [[ion]] ([[cation]]), the name of the compound is simply the cation's name (usually the same as the element's), followed by the anion. For example, NaCl is ''sodium chloride'', and CaF<sub>2</sub> is ''calcium fluoride''. # Cations able to take on more than one positive charge are labeled with [[Roman numerals]] in parentheses. For example, Cu<sup>+</sup> is copper(I), Cu<sup>2+</sup> is copper(II). An older, deprecated notation is to append ''-ous'' or ''-ic'' to the root of the Latin name to name ions with a lesser or greater charge. Under this naming convention, Cu<sup>+</sup> is cuprous and Cu<sup>2+</sup> is cupric. For naming metal complexes see the page on [[complex (chemistry)]]. # [[Oxyanion]]s (polyatomic anions containing oxygen) are named with ''-ite'' or ''-ate'', for a lesser or greater quantity of oxygen. For example, NO<sub>2</sub><sup>−</sup> is nitrite, while NO<sub>3</sub><sup>−</sup> is nitrate. If four oxyanions are possible, the prefixes ''hypo-'' and ''per-'' are used: hypochlorite is ClO<sup>−</sup>, perchlorate is ClO<sub>4</sub><sup>−</sup>, # The prefix ''bi-'' is a [[deprecated]] way of indicating the presence of a single [[hydrogen]] ion, as in "sodium bicarbonate" (NaHCO<sub>3</sub>). The modern method specifically names the hydrogen atom. Thus, NaHCO<sub>3</sub> would be pronounced "sodium hydrogen carbonate". Positively charged ions are called [[cation]]s and negatively charged ions are called [[anion]]s. The cation is '''always''' named first. Ions can be metals or polyatomic ions. Therefore the name of the metal or positive polyatomic ion is followed by the name of the non-metal or negative polyatomic ion. The positive ion retains its element name whereas for a single non-metal anion the ending is changed to -ide. Example: sodium chloride, potassium oxide, or calcium carbonate. When the metal has more than one possible ionic charge or [[oxidation number]] the name becomes [[ambiguous]]. In these cases the oxidation number of the metal ion is represented by a Roman numeral in parentheses immediately following the metal ion name. For example in uranium(VI) fluoride the [[oxidation number]] of [[uranium]] is 6. Another example is the iron oxides. FeO is iron(II) oxide and Fe<sub>2</sub>O<sub>3</sub> is iron(III) oxide. An older system used prefixes and suffixes to indicate the oxidation number, according to the following scheme: {| class="wikitable" |- ! Oxidation state ! Cations and acids ! Anions |- | Lowest || hypo- -ous || hypo- -ite |- | &nbsp; || -ous || -ite |- | &nbsp; || -ic || -ate |- | Highest || per- -ic || per- -ate |} Thus the four oxyacids of [[chlorine]] are called hypochlorous acid (HOCl), chlorous acid (HOClO), chloric acid (HOClO<sub>2</sub>) and perchloric acid (HOClO<sub>3</sub>), and their respective [[conjugate acid|conjugate base]]s are the hypochlorite, chlorite, chlorate and perchlorate ions. This system has partially fallen out of use, but survives in the [[common name]]s of many [[chemical compound]]s: the modern literature contains few references to "ferric chloride" (instead calling it "iron(III) chloride"), but names like "potassium permanganate" (instead of "potassium manganate(VII)") and "sulfuric acid" abound. ==Traditional naming== === Naming simple ionic compounds === An ionic compound is named by its cation followed by its anion. See [[polyatomic ions]] for a list of possible ions. For cations that take on multiple charges, the charge is written using [[Roman numeral]]s in parentheses immediately following the element name) For example, Cu(NO<sub>3</sub>)<sub>2</sub> is ''[[copper(II) nitrate]]'', because the charge of two [[nitrate]] ions (NO<sub>3</sub><sup>-1</sup>) is 2 × −1 = −2, and since the net charge of the [[ionic compound]] must be zero, the Cu ion has a 2+ charge. This compound is therefore copper(II) nitrate. In the case of cations with a 4+ oxidation state, the acceptable format for the Roman numeral 4 is IV and not IIII. The [[Roman numeral]]s in fact show the [[oxidation number]], but in simple ionic compounds (i.e., not [[Complex (chemistry)|metal complexes]]) this will always equal the ionic charge on the metal. For a simple overview see [http://www.cofc.edu/~deavorj/101/nomenclature.html], for more details see [http://www2.potsdam.edu/walkerma/inorg_naming.pdf selected pages from IUPAC rules for naming inorganic compounds]. ====List of common ion names==== Monatomic anions: :Cl<sup>−</sup> [[chloride]] :S<sup>2−</sup> [[sulfide]] :P<sup>3−</sup> [[phosphide]] [[Polyatomic ion]]s: :NH<sub>4</sub><sup>+ </sup> [[ammonium]] :H<sub>3</sub>O<sup>+</sup> [[hydronium]] :NO<sub>3</sub><sup>− </sup> [[nitrate]] :NO<sub>2</sub><sup>−</sup> [[nitrite]] :ClO<sup>−</sup> [[hypochlorite]] :ClO<sub>2</sub><sup>−</sup> [[chlorite]] :ClO<sub>3</sub><sup>−</sup> [[chlorate]] :ClO<sub>4</sub><sup>−</sup> [[perchlorate]] :SO<sub>3</sub><sup>2− </sup> [[sulfite]] :SO<sub>4</sub><sup>2−</sup> [[sulfate]] :HSO<sub>3</sub><sup>−</sup> [[hydrogen sulfite]] (or [[bisulfite]]) :HCO<sub>3</sub><sup>−</sup> [[hydrogen carbonate]] (or [[bicarbonate]]) :CO<sub>3</sub><sup>2−</sup> [[carbonate]] :PO<sub>4</sub><sup>3−</sup> [[phosphate]] :HPO<sub>4</sub><sup>2−</sup> [[hydrogen phosphate]] :H<sub>2</sub>PO<sub>4</sub><sup>−</sup> [[dihydrogen phosphate]] :CrO<sub>4</sub><sup>2−</sup> [[chromate]] :Cr<sub>2</sub>O<sub>7</sub><sup>2−</sup> [[dichromate]] :BO<sub>3</sub><sup>3−</sup> [[orthoborate]] :AsO<sub>4</sub><sup>3− </sup> [[arsenate]] :C<sub>2</sub>O<sub>4</sub><sup>2−</sup> [[oxalate]] :CN<sup>−</sup> [[cyanide]] :SCN<sup>−</sup> [[thiocyanate]] :MnO<sub>4</sub><sup>−</sup> [[permanganate]] === Naming hydrates === [[Hydrate]]s are ionic compounds that have absorbed water. They are named as the ionic compound followed by a numerical prefix and ''-hydrate''. The numerical prefixes used are listed below: # [[Wiktionary:mono-|mono-]] # [[Wiktionary:di-|di-]] # [[Wiktionary:tri-|tri-]] # [[Wiktionary:tetra-|tetra-]] # [[Wiktionary:penta-|penta-]] # [[Wiktionary:hexa-|hexa-]] # [[Wiktionary:hepta-|hepta-]] # [[Wiktionary:octa-|octa-]] # [[Wiktionary:nona-|nona-]] # [[Wiktionary:deca-|deca-]] For example, CuSO<sub>4</sub> · 5H<sub>2</sub>O is "copper(II) sulfate pentahydrate". === Naming molecular compounds === Inorganic molecular compounds are named with a prefix (see list above) before each element. The more [[electronegativity|electronegative]] element is written last and with an ''-ide'' suffix. For example, CO<sub>2</sub> is ''carbon dioxide''. Although CCl<sub>4</sub> is sometimes called ''carbon tetrachloride'' under this rule, it is not an inorganic molecule and is more properly called tetrachloromethane. There are some exceptions to the rule, however. The prefix '''mono-''' is not used with the first element; for example, CO<sub>2</sub> is ''carbon dioxide'', not "monocarbon dioxide". Sometimes prefixes are shortened when the ending vowel of the prefix "conflicts" with a starting vowel in the compound. This makes the compound easier to speak; for example, CO is "carbon monoxide" (as opposed to "monooxide"). === Naming acids === Acids are named by the anion they form when dissolved in water. If an acid forms an anion named ''___ide'', it is named ''hydro___ic acid''. For example, ''hydro''chlor''ic acid'' forms a chlor''ide'' anion. With sulfur, however, the whole word is kept instead of the root: i.e.: ''hydro''sulfur''ic acid''. Secondly, anions with an ''-ate'' suffix are formed when acids with an ''-ic'' suffix are dissolved, e.g. [[Chloric acid|chlor''ic'' acid]] ([[Hydrogen|H]][[Chlorine|Cl]][[Oxygen|O]]<sub>3</sub>) dissociates into chlor''ate'' anions to form salts such as [[Sodium chlorate|sodium chlor''ate'']] ([[Sodium|Na]][[Chlorine|Cl]][[Oxygen|O]]<sub>3</sub>); anions with an ''-ite'' suffix are formed when acids with an ''-ous'' suffix are dissolved in water, e.g. [[Chlorous acid|chlor''ous acid'']] (HClO<sub>2</sub>) disassociates into chlor''ite'' anions to form salts such as [[Sodium chlorite|sodium chlor''ite'']] (NaClO<sub>2</sub>). == 2005 revision of [[IUPAC]]'s nomenclature for inorganic compounds == See main article [[IUPAC nomenclature of inorganic chemistry 2005]] == See also == *[[IUPAC nomenclature]] *[[IUPAC nomenclature of organic chemistry]] *[[List of inorganic compounds]] *[[Water of Crystallization]] == References == #{{note|RedBook}} ''Nomenclature of Inorganic Chemistry, Recommendations 1990'', Oxford:Blackwell Scientific Publications. (1990) == External links == *[http://www.iupac.org/reports/provisional/abstract04/connelly_310804.html IUPAC Provisional Recommendations for the Nomenclature of Inorganic Chemistry (2004)] (online draft of an updated version of the "''Red Book''") *[http://www.chem.qmul.ac.uk/iupac/bibliog/inorg.html Bibliography of IUPAC Recommendations on Inorganic Nomenclature] (last updated [[2004-02-17]]) *[http://dbhs.wvusd.k12.ca.us/webdocs/Nomenclature/Nomenclature.html ChemTeam Highschool Tutorial] *[http://www2.potsdam.edu/walkerma/inorg_naming.pdf PDF file SUNY Potsdam.edu] *[http://www.miramar.sdccd.cc.ca.us/faculty/fgarces/ChemComon/Tutorial/ChemNomen/ChemNomenclature.htm Nomenclature Tutorial] [[Category:Chemical nomenclature]] [[Category:Inorganic chemistry]] [[cs:Anglické chemické názvosloví]] [[es:Nomenclatura química de los compuestos inorgánicos]] [[id:Tatanama anorganik]] [[pt:Nomenclatura química]] [[zh:无机化学命名法]]