Naming Inorganic Compounds Section 2.8 Naming Inorganic Compounds

Chemical Nomenclature Naming system of substances Latin: Nomen~ name Calare~ to call Two main categories: Organic and Inorganic

Inorganic Compound Rules Ionic Molecular Acids

Ionic Compounds Cations Anions Compounds

Ionic Compounds 1. Cations a) Same name as the metal they formed from: Na+ sodium ion b) Metals forming different cations: use Roman numerals in parentheses: Fe2+ iron (II) ion Fe 3+ iron (III) ion ~ Older method: -ous or –ic ending Fe2+ ferrous ion Fe3+ ferric ion

Ionic Compounds c) Cations formed from nonmetal atoms have names that end in –ium NH4+ ammonium ion H3O+ hydronium ion

Ionic Compounds 2. Anions O2- oxide N3- nitride NO3- nitrate a) Monoatomic anions are formed by replacing ending of name of element with –ide O2- oxide N3- nitride b) Polyatomic anions contain oxygen (oxyanions) end in –ate or –ite NO3- nitrate NO2- nitrite

Ionic Compounds NO3- nitrate NO2- nitrite ClO4- perchlorate b) Polyatomic anions contain oxygen (oxyanions) end in –ate or –ite -ite has one fewer O atoms than an –ate NO3- nitrate NO2- nitrite Prefixes per- and –hypo are used when there are more than four members ClO4- perchlorate ClO3- chlorate ClO2- chlorite ClO- hypochlorite

Ionic Compounds c) Anions derived from adding H+ to an oxyanion: begin with either hydrogen or dihydrogen CO32- carbonate HCO3- hydrogen carbonate PO43- phosphate H2PO43- dihydrogen phosphate

Ionic Compounds 3. Compounds Names consist of the cation name followed by the anion name CaCl2 calcium chloride AlPO3 aluminum phosphite CuSO4 copper (II) sulfate

Acids -ides -ates /-ites

Acids 1. With anions ending in –ide: change –ide to –ic, add the prefix hydro-, and follow with the word acid Anion Corresponding Acid Cl- (chloride) HCl (hydrochloric acid) S2- (sulfide) H2S (hydrosulfuric acid

Acids 2. With anions ending in –ate or –ite: Change –ate to –ic Change –ite to –ous Add the word acid Anion Corresponding Acid ClO4- (perchlorate) HClO4 (perchloric acid) ClO3- (chlorate) HClO3 (chloric acid) ClO2- (chlorite) HClO2 (chlorous acid) ClO- (hypochlorite) HClO (hypochorous acid)

Molecular Compounds (Binary) 1. Name the element farther to the left in the periodic table first. 2. If both in same group, the one with the higher atomic number is named first. 3. Name the second with an –ide ending 4. Greek prefixes are used to indicate number of atoms of each element