Polyatomic Ions and Compounds

Have You Ever…  Heard of things like sodium bicarbonate or sodium hydroxide ?  How about baking soda or lye

Polyatomic Ions  Do not exist on the periodic table  Are special groups of elements  Multiple elements that group together and react as one

Polyatomic Ions – Do NOT Copy Name of Polyatomic Ion FormulaIonic Chage AMMONIUMNH 4 1+ NITRATENO 3 1- HYDROXIDEOH1- BICARBONATEHCO 3 1- CHLORATEClO 3 1- CARBONATECO 3 2- SULFATESO 4 2- PHOSPHATEPO 4 3-

Naming Polyatomic Compounds 1. Write the name of the cation (usually the metal or NH 4 ) 2. Write the name of the anion (usually the polyatomic group) E.G. Ca(OH) 2 Na 2 SO 4 (NH 4 ) 2 O

Naming Polyatomic Compounds 1. Write the name of the cation (usually the metal or NH 4 ) 2. Write the name of the anion (usually the polyatomic group) E.G. Ca(OH) 2 calcium hydroxide Na 2 SO 4 (NH 4 ) 2 O

Naming Polyatomic Compounds 1. Write the name of the cation (usually the metal or NH 4 ) 2. Write the name of the anion (usually the polyatomic group) E.G. Ca(OH) 2 calcium hydroxide Na 2 SO 4 sodium sulfate (NH 4 ) 2 O

Naming Polyatomic Compounds 1. Write the name of the cation (usually the metal or NH 4 ) 2. Write the name of the anion (usually the polyatomic group) E.G. Ca(OH) 2 calcium hydroxide Na 2 SO 4 sodium sulfate (NH 4 ) 2 Oammonium oxide (if it is a non-metal – “ide”)

Writing the Chemical Formula of a Polyatomic Compound 1. Write the symbol of the cation 2. Write the symbol of the anion 3. Write the charge of each (the element and the group) 4. Criss-cross the charge # to the bottom 5. Re-write and reduce if needed

Examples 1. Calcium Nitrate 2. Beryllium Carbonate