1. Chapter 5: Nomenclature Chemistry 1020: Interpretive chemistry Andy Aspaas, Instructor

2. Binary ionic compounds Ionic compound: combination of metal cation and nonmetal anion Main-group metals in groups 1, 2, and 3 –Form cations, charge can be predicted by group number –Metal cations have the same name as the element Nonmetal: take root of element name and add -ide –Charge predicted by taking 8 - group number In naming compounds, cation is named first and anion second

3. Ionic compounds with transition metal cations Transition metals can produce ions with varying charges When naming these compounds, you must indicate the charge of the cation in roman numerals after the cation name –Ex. PbCl 2 must have Pb 2+ cations –Name: lead(II) chloride

4. Compounds containing only nonmetals Binary compounds with only nonmetals are one type of molecules The first element given in the formula is named first, with its full name The second element is named as if it were an anion Use Greek prefixes to denote subscripts –1=mono, 2=di, 3=tri, 4=tetra, 5=penta, 6=hexa, 7=hepta, 8=octa

5. Polyatomic ions Polyatomic ion: a molecule (composed of 2 or more atoms) that carries a charge Oxyanion: one atom of a given element, bonded to different numbers of oxygen atoms. –If there are 2 different oxyanions for a given element, use suffixes to differentiate their name –“ite” for ion with fewer oxygens –“ate” for ion with greater number of oxygens

6. Polyatomic ions

7. Use prefixes if more than one oxyanion for an element ClO – hypochlorite ClO 2 – chlorite ClO 3 – chlorate ClO 4 – perchlorate Oxyanions for a given element have the same charge, but added hydrogens decrease the charge CO 3 2– carbonate HCO 3 – hydrogen carbonate, or bicarbonate

8. Nomenclature of compounds with polyatomic ions Type 1: Cation has known charge –Use cation name and anion name –Ex. Na 2 CO 3, KH 2 PO 4, NH 4 ClO 3, Al 2 (SO 3 ) 3 Type 2: Cation has several possible charges –Use cation name and roman numeral for cation charge, then anion name –Ex. CuSO 4, Fe(CN) 3, Ti(CrO 4 ) 2, Ag 2 SO 3

9. Nomenclature of acids Acid: compound with one or more H + ions attached to an anion –Acids which do not contain oxygen Name hydro ______ic acid (with element root in the blank) HF, HCl, HBr, H 2 S –Acids which contain oxygen Use oxyanion name, but change suffix “ite” becomes “ous” “ate” becomes “ic” H 2 SO 4, H 2 SO 3, HNO 2, H 3 PO 4