3.2 Names and Formulas of Ionic Compounds (c) McGraw Hill Ryerson 2007 See page 85 INCREASING REACTIVITY

Naming Simple Ionic Compounds  Rules for naming simple ionic compounds: 1. Write the name of the metal (positive ion) first. 2. Write the name of the non-metal (negative ion) second. 3. Change the ending of the non-metal ion to “ide.” (c) McGraw Hill Ryerson 2007

Naming Simple Ionic Compounds  Examples: Li 3 N__________________________ MgBr 2 __________________________ Ag 2 O __________________________ CdS __________________________ (c) McGraw Hill Ryerson 2007

Naming Simple Ionic Compounds (c) McGraw Hill Ryerson 2007

Writing Formulas for Simple Ionic Compounds  Rules for writing formulas for ionic compounds: 1. STEP ONE: Write the symbol for the more metallic element first. Then, write the symbol for the non-metallic element. 2. STEP TWO: Write the combining capacities for the elements. Ignore the + and – charges. *If there is no #, the combining capacity is STEP THREE: Swap and drop the combining capacities to get the subscripts. (c) McGraw Hill Ryerson 2007

Writing Formulas for Simple Ionic Compounds  Examples: Barium phosphide ______________ Aluminum nitride ______________ Zinc oxide ______________ Rubidium bromide ______________ (c) McGraw Hill Ryerson 2007

Multivalent Metal Compounds  Many metals are multivalent, meaning the metals form two or more different positive ions with different charges.  For example, the atom iron forms two ions Fe 2+ and Fe 3+. (c) McGraw Hill Ryerson 2007 See page 88

Multivalent Metal Compounds  To distinguish different ions for the same metal, roman numerals are added to their name. For example, Fe 3+ would be named “iron(III)” (c) McGraw Hill Ryerson 2007

Writing Formulas for Ionic Compounds Containing Multivalent Metals (c) McGraw Hill Ryerson 2007 See page 89 easywrite the formulas tell you their combining capacities  It is easy to write the formulas for multivalent ionic compounds, because they tell you their combining capacities so you don’t need to look on the periodic table.

Writing Formulas for Ionic Compounds Containing Multivalent Metals  Examples: Iron (II) phosphide ______________ Manganese (II) oxide ______________ Tin (II) sulfide ______________ Lead (IV) chloride ______________ (c) McGraw Hill Ryerson 2007

Naming Ionic Compounds Containing Multivalent Metals more difficult to name work backwards ROMAN NUMERAL It is a little more difficult to name a multivalent ionic compound, because you have to work backwards to figure out which combining capacity was used. Remember to use a ROMAN NUMERAL!!! (c) McGraw Hill Ryerson 2007 See page 90

Naming Ionic Compounds Containing Multivalent Metals  Examples: Fe 2 O 3 __________________________ PbF 4 __________________________ MnS__________________________ TiS 2 __________________________ (c) McGraw Hill Ryerson 2007

Naming Ionic Compounds Containing Polyatomic Ions more than two elementspolyatomic ion find When you are naming compounds with more than two elements, you are dealing with a polyatomic ion. All you need to do, is find it in the chart so you can name your compound. positive charge metalcomes first 1. If the polyatomic ion group has a positive charge (+) it acts like a metal and comes first in the name. non-metal second 2. If the polyatomic ion group has a negative charge (-) it acts like a non-metal and comes second in the name. (c) McGraw Hill Ryerson 2007

Naming Ionic Compounds Containing Polyatomic Ions  Examples: Fe(OH) 3 ________________________ Mg 3 (PO 4 ) 2 ________________________ (NH 4 ) 3 P ________________________ Ca(CH 3 COO) 2 ________________________ (c) McGraw Hill Ryerson 2007 See page 91

Writing Formulas for Ionic Compounds Containing Polyatomic Ions has its own combining capacity Each polyatomic ion has its own combining capacity that should be used when writing a chemical formula. USE BRACKETS AROUND THE POLYATOMIC IONS USE BRACKETS AROUND THE POLYATOMIC IONS!! (c) McGraw Hill Ryerson 2007 See page 91

Writing Formulas for Ionic Compounds Containing Polyatomic Ions  Examples: Sodium chromate________________ Ammonium nitrate ________________ Lead (II) perchlorate ________________ Tin (II) cyanide ________________ (c) McGraw Hill Ryerson 2007 See page 91 Section 3.2 Quiz