IONIC BONDS What are Ionic and Covalent Bonds? Naming Simple Ionic Compounds Writing Simple Ionic formulas

Bonds: Chemical Bond – a force that holds two atoms together Caused by: Attraction between ions Attraction of a positively charged nucleus and the negatively charged electrons of a different atom.

Bonds: Ionic and Covalent Ionic Compounds A bond between two elements where electrons are transferred from one element to another Covalent Compounds A bond between two elements where electrons are shared between the elements Bonds form between the valence electrons of each atom!

Ionic Bonds: Ionic bonds are formed between ions, and include both a metal and a nonmetal. Ion: a charged particle Cation: loses one or more electrons to become positively charged (metals) Anion: gains one or more electrons to become negatively charged (nonmetals)

Ionic Bonds/Compounds: Simple Ionic Compounds are also known as Binary Compounds There are ONLY 2 elements present Always a metal and a nonmetal The elements always come from the s and p blocks on the periodic table.

Naming Simple Ionic Compounds: The name of the metal ALWAYS comes first The metal’s name is the same as it is on the periodic table The name of the nonmetal ALWAYS comes last The nonmetal’s name changes. The ending of the nonmetal will change to “ide” Na2O Name the metal directly (rule 1): Sodium Change the ending of the nonmetal (rule 2): oxide Sodium Oxide

Naming Simple Ionic Compounds: Simple Ionic Compound Formula Ionic Compound Name KF Al2O3 CaBr2 Li3P Li2S

Oxidation Numbers/States: What are the charges of each family? +1 +2 +3 +/- 4 -3 -2 -1

Ionic Bonds: Writing Compounds Compounds MUST be neutral Charges MUST cancel each other Add up the charges until you get 0 The metal (cation) ALWAYS comes first The nonmetal (anion) ALWAYS comes second

Example: Sodium (Na+1) and Oxygen (O -2) Oxygen’s -2 charge needs to be cancelled out by sodium’s +1 charge. We will need 2 sodium ions to cancel the 1 oxygen ion. +1 + 1 + -2 = 0 (this would be neutral) So our compounds formula is: Na2O (2 sodium ions and 1 oxygen ion)

Drop and Swap: The method that is used to write the proper formulas for different ionic compounds is the drop and swap. Bring down and over the numerical value (WITHOUT the charge sign) Na2O DO NOT WRITE THE 1’S

Calcium (+2) and Oxygen (-2) Drop and Swap: Subscripts MUST be at the simplest whole number ratio Calcium (+2) and Oxygen (-2) Ca+2 O-2 Ca2O2 CaO

Drop and Swap Practice: Metal Nonmetal Drop and Swap Form Simplest Whole Number Ratio Form Calcium Fluorine Barium Sulfur Lithium Phosphorous Magnesium Oxygen Boron Cesium