Naming Ionic Compounds

Remember… Metals form positive ions or cation. The charges on ions formed from groups 1A, 2A and the upper part of 3A is the same as the group number. Hydrogen can have a +1 or a -1 charge.

Remember… Transition metals have a variable charge. Example: Iron can have a +2 or a +3 charge depending on the compound. EXCEPTION: Zn, Cd, Ag are not transition metals; ALWAYS Zn2+, Cd2+, and Ag+1

Remember… Non-metals form negative ions or anions The charge on ions formed from group 7A is -1, 6A is -2 and 5A is -3.

Ionic Compounds (metal and a non metal) If given the Formula, to write the name you must… The full name of the cation is listed first. If the compound is a transition metal, you must determine its’ charge. Include a roman numeral after the name to indicate the charge of the metal. Then list root of the anion name with the suffix “ide.”

Naming Binary Ionic Compounds Examples: NaCl BaF2 CuO Na2O CaBr2 CuCl2 sodium chloride sodium oxide barium fluoride calcium bromide copper (II) oxide copper (II) chloride

Ionic Compounds (metal and a non metal) If given the Name, to write the formula you must… Write the symbol of the first ion in the compound’s name, then the symbol of the second ion in the compound ’s name. Indicate the ratio of each ion in the compound using subscripts after each ion. Note: The ratio of the ions are determined by balancing the charges of the ions.

Naming Binary Ionic Compounds Examples: Lithium Iodide Gallium Chloride Lead (II) Nitride Sodium hydride Magnesium Oxide Tin (IV) sulfide LiI NaH GaCl3 MgO Pb3N2 SnS2

Polyatomic Ion A charged particle with two or more atoms held together. Example: SO42-

Rules for Polyatomic Ions Naming/Writing Formulas Same rules EXCEPT: Naming - You will NOT change the suffix to “ide”; write the name of the polyatomic ion as is. Formulas - Use parentheses when the simplest ratio requires more than one polyatomic ion in the compound formula.

Naming Binary Ionic Compounds with Polyatomic Ions ammonium phosphate iron (II) phosphate ammonium carbonate CaCO3 K2CrO4 Fe(OH)3 calcium carbonate (NH4)3PO4 potassium chromate Fe3(PO4)2 iron (III) hydroxide (NH4)2CO3