Summary of Naming Rules

Naming Ionic Compounds Rule number #1: Make sure you actually have an ionic compound or not! Example: CrO consists of chromium and Oxygen An Ionic Compound must have a METAL (except in the case of ammonium NH 4 +1 ) and a NON-METAL metal non-metal

Rule number #2: Write out the correct names for the parts of the ionic compound Example: CrO Cr is NOT Chlorine or Carbon or Cryptonite! It is chromium! chromium and oxygen

Rule number #3:Put an –ide on the ending of the non-metal if it is just an monatomic anion such as Cl or Br or F. Example: Chromium Oxide CrO

Rule number #4: Figure out if you need a Roman numeral in the name. CrO Cr definitely can have more than one charge: Cr +2 or Cr +3 so a roman numeral is needed Cr +2 or Cr +3

Rule number #3: Figure out what the Roman numeral should be. Cr O -2 chromium oxide Oxygen ALWAYS has a charge of -2 Therefore the Cr has to be +2 the formula is: Chromium (II) Oxide ? ?

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