Binary Ionic Compounds

Ionic Compounds ions of opposite charge chemically bonded together Electrons are transferred from one element to the next bonds form between anions (-) and cations (+) OR bonds form between metals and nonmetals bonded together so that the net charge (oxidation number) of the atom is zero

Atoms will combine in compounds to make every element have a total of 8 valence

Basic Properties of Ionic Compounds Electrolytes Conduct electricity in aqueous solution Dissolve well in water Solid crystal at room temperature Strong interparticle forces

Binary Ionic Compounds Ionic compound formed from two elements (can contain more than one atom of each element) Examples: NaCl MgBr2

Naming Binary Ionic Compounds Name metal first (positive ion) Then add the name of the nonmetal (negative ion) but change the ending to “ide” Ending is usually the last syllable Example: sodium (Na) and chlorine (Cl) Name: Sodium Chloride Chemical Formula: NaCl

Practice Problem 1: Name the ionic compound shown below: MgF2 Magnesium fluoride

Practice Problem 2: Name the ionic compound shown below: Li2O Lithium oxide

Writing Chemical Formulas for Binary Ionic Compounds Write the symbol for each element with it’s oxidation number (charge) Remember: write metal first Chemical formulas of ionic compounds are always neutral (so oxidation numbers must balance) Add subscripts to the symbols for the ions until the sum of the charges is equal to zero No subscripts are needed if only one ion is present

Example: Calcium Chloride Ca+2 Cl-1 CaCl2

Practice Problem 3: Write the chemical formula for aluminum bromide.

Practice Problem 4: Write the chemical formula for magnesium nitride.

Practice Problem 5 Write the chemical formula for calcium oxide.