Ionic Compounds

Ionic Compounds Ion: Any atom that has a charge Cation: An ion with a + charge anion: An ion with a - charge

A bond that forms between (+) metals and (-) non metals. Ionic Bonds A bond that forms between (+) metals and (-) non metals. Electrons are transferred and then the opposite charges attract.

Elements want 8 valence electrons Octet Rule Element always move to become more stable. Most elements change their electron configuration to match the configuration of noble gasses. Elements want 8 valence electrons

1+ 2+ 3+ 3- 2- 1-

Rules for Writing Ionic Compounds 1.Charge must always cancel out + and – charges add up to zero. 2. Find the charges from the periodic table or the chart.

Rules for Writing Ionic Compounds 3.If the charges are the same they cancel out and it is a one to one ratio. Ca1O1 Ca2+ , O2-

4.If they are not find the least common mutiple Ca2+ Cl1- = 2 The number that goes in the formula is what you would multiple the charge by to equal the L. C. M. Ca1Cl2

Rules for Writing Ionic Compounds Or… reduce the charges and use the cross rule Sn4+ O2- Ca2+ Cl1- Sn2+ O1- Sn2+ O1- Ca1Cl2 Sn1O2

Rules for Naming Ionic Compounds 1. The first element (metal) name does not change. 2. The second elements name ending changes to -ide NaO MgCl2 Al2S3

Rules for Naming Ionic Compounds (except for polyatomic ions, use the name on the chart) SO42- = sulfate Na2SO4 = sodium sulfate

Rules for Naming Ionic Compounds 3. If it is a transition metal Roman Numerals must be used. FeCl2 FeCl FeCl3 The Roman numeral tells you the charge of the transition metal

Rules for Naming Ionic Compounds 4. There are no prefixes in ionic compounds