Traditional naming Simple ionic compounds Īn ionic compound is named by its cation followed by its anion. This system has partially fallen out of use, but survives in the common names of many chemical compounds: 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. Thus the four oxyacids of chlorine are called hypochlorous acid (HOCl),Ĭhlorous acid (HOClO), chloric acid (HOClO 2) and perchloric acid (HOClO 3), and their respective conjugate bases are hypochlorite, chlorite, chlorate and perchlorate ions. FeO is iron(II) oxide and Fe 2O 3 is iron(III) oxide.Īn older system used prefixes and suffixes to indicate the oxidation number, according to the following scheme: For example, in uranium(VI) fluoride the oxidation number of uranium is 6. In these cases the oxidation number (the same as the charge) of the metal ion is represented by a Roman numeral in parentheses immediately following the metal ion name. When the metal has more than one possible ionic charge or oxidation number the name becomes ambiguous. The positive ion retains its element name whereas for a single non-metal anion the ending is changed to -ide.Įxample: sodium chloride, potassium oxide, or calcium carbonate. Therefore, the name of the metal or positive polyatomic ion is followed by the name of the non-metal or negative polyatomic ion. Ions can be metals, non-metals or polyatomic ions. Positively charged ions are called cations and negatively charged ions are called anions. Thus, NaHCO 3 would be pronounced sodium hydrogen carbonate. The modern method specifically names the hydrogen atom. The prefix bi- is a deprecated way of indicating the presence of a single hydrogen ion, as in " sodium bicarbonate" (NaHCO 3).If four oxyanions are possible, the prefixes hypo- and per- are used: hypochlorite is ClO −, perchlorate is ClO − Oxyanions (polyatomic anions containing oxygen) are named with -ite or -ate, for a lesser or greater quantity of oxygen, respectively.For naming metal complexes see the page on complex (chemistry). Under this naming convention, Cu + is cuprous and Cu 2+ is cupric. 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. For example, Cu + is copper(I), Cu 2+ is copper(II). Cations of transition metals able to take multiple charges are labeled with Roman numerals in parentheses to indicate their charge.For example, NaCl is sodium chloride, and CaF 2 is calcium fluoride. 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.Single atom anions are named with an -ide suffix: for example, H − is hydride.Similarly, H 2O is most often simply called water in English, though other chemical names do exist.
#CHEMISTRY SYMBOL AG CHARGE PROFESSIONAL#
However, for the sake of brevity, 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. These advantages make the systematic name far superior to the common name when absolute clarity and precision are required.
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. The names " caffeine" and " 3,7-dihydro-1,3,7-trimethyl-1H-purine-2,6-dione" both signify the same chemical compound. There is also an IUPAC nomenclature of organic chemistry. Ideally, every inorganic compound should have a name from which an unambiguous formula can be determined. It is published in Nomenclature of Inorganic Chemistry (which is informally called the Red Book). In chemical nomenclature, the IUPAC nomenclature of inorganic chemistry is a systematic method of naming inorganic chemical compounds, as recommended by the International Union of Pure and Applied Chemistry (IUPAC). For the current Red Book version, see IUPAC nomenclature of inorganic chemistry 2005.
0 kommentar(er)
