Naming Compounds and Formulas
Naming Ionic Compounds When naming ionic compounds, the cation’s name always comes before the name of the anion – Sodium (+1) Chloride (-1)
Naming Ionic Compounds Use the symbol of the cation first, followed by the elemental symbol for the anion Use subscripts to show the ratio of the ions in the compound – Sodium Sulfide = (Na 2 S)
In the bonding of an Ionic compound, the anion’s name will always end in an –ide Examples: Sodium Chloride and Magnesium Oxide
Metals with Multiple Ions Some transition metals will form more than one ion – Some form one ion and some form 2 or 3 ions We use roman numerals to indicate the charge of the ion – Iron (III) has a charge of +3
Metals with Multiple Ions CuO In this compound containing copper we can figure out that the copper being used is copper(II) because 2 positive charges are needed to neutralize oxygen’s -2 charge
Rules for Naming Covalent Compounds The element that appears most “left” on the periodic table appears first in the compound name Example: Hydrogen Chloride
If you have more than one atom of an element, we use prefixes to name them We usually DO NOT include the mono- prefix in the first element
For Example: – Dihydrogen Monoxide 2 Hydrogen and 1 Oxygen
We also add the ending –ide to bonds including two non-metals (all covalent bonds) Example: Carbon Monoxide