1. POLYATOMIC IONS 3-2- 1-

2. a group of atoms that act as a single ion they carry an overall ionic charge they stick together when they combine with other ions to form ionic compounds July 2, 20162 Polyatomic Ions Polyatomic Ion Ion Formula Ionic Charge

3. a group of atoms that act as a single ion they carry an overall ionic charge they stick together when they combine with other ions to form ionic compounds July 2, 20163 Polyatomic Ions Polyatomic Ion Ion Formula Ionic Charge ammonium NH 4 + +1

4. a group of atoms that act as a single ion they carry an overall ionic charge they stick together when they combine with other ions to form ionic compounds July 2, 20164 Polyatomic Ions Polyatomic Ion Ion Formula Ionic Charge ammonium NH 4 + +1 nitrate NO 3 -

5. a group of atoms that act as a single ion they carry an overall ionic charge they stick together when they combine with other ions to form ionic compounds July 2, 20165 Polyatomic Ions Polyatomic Ion Ion Formula Ionic Charge ammonium NH 4 + +1 nitrate NO 3 - hydroxide OH -

6. a group of atoms that act as a single ion they carry an overall ionic charge they stick together when they combine with other ions to form ionic compounds July 2, 20166 Polyatomic Ions Polyatomic Ion Ion Formula Ionic Charge ammonium NH 4 + +1 nitrate NO 3 - hydroxide OH - bicarbonate HCO 3 -

7. a group of atoms that act as a single ion they carry an overall ionic charge they stick together when they combine with other ions to form ionic compounds July 2, 20167 Polyatomic Ions Polyatomic Ion Ion Formula Ionic Charge ammonium NH 4 + +1 nitrate NO 3 - hydroxide OH - bicarbonate HCO 3 - chlorate ClO 3 -

8. a group of atoms that act as a single ion they carry an overall ionic charge they stick together when they combine with other ions to form ionic compounds July 2, 20168 Polyatomic Ions Polyatomic Ion Ion Formula Ionic Charge ammonium NH 4 + +1 nitrate NO 3 - hydroxide OH - bicarbonate HCO 3 - chlorate ClO 3 - carbonate CO 3 2- -2

9. a group of atoms that act as a single ion they carry an overall ionic charge they stick together when they combine with other ions to form ionic compounds July 2, 20169 Polyatomic Ions Polyatomic Ion Ion Formula Ionic Charge ammonium NH 4 + +1 nitrate NO 3 - hydroxide OH - bicarbonate HCO 3 - chlorate ClO 3 - carbonate CO 3 2- -2 sulfate SO 4 2- -2

10. a group of atoms that act as a single ion they carry an overall ionic charge they stick together when they combine with other ions to form ionic compounds July 2, 201610 Polyatomic Ions Polyatomic Ion Ion Formula Ionic Charge ammonium NH 4 + +1 nitrate NO 3 - hydroxide OH - bicarbonate HCO 3 - chlorate ClO 3 - carbonate CO 3 2- -2 sulfate SO 4 2- -2 phosphate PO 4 3- -3

11. Writing Formulas of Polyatomic Compounds Don’t Copy 1. Write the symbol for each ion (positive ion always goes 1 st ) 2. Add the ionic charge at the top of each symbol 3. Crisscross rule to figure out the formula of the compound formed 4. If there is more than 1 polyatomic ion, you must put a bracket around it, before writing the subscript (outside the bracket) July 2, 201611

12. Writing Formulas of Polyatomic Compounds polyatomic compounds are usually composed of a metal ion and a polyatomic ion Examples: 1. sodium sulfate July 2, 201612 Na + SO 4 2- Na 2 SO 4 Na 2 SO 4

13. Writing Formulas of Polyatomic Compounds 2. magnesium hydroxide July 2, 201613 Mg 2+ OH - Mg(OH) 2 Mg(OH) 2

14. Writing Formulas of Polyatomic Compounds 3. ammonium iodide July 2, 201614 NH 4 + I - NH 4 I

15. Writing Formulas of Polyatomic Compounds 4. calcium phosphate July 2, 201615 Ca 2+ PO 4 3- Ca 3 (PO 4 ) 2 Ca 3 (PO 4 ) 2

16. Writing Formulas of Polyatomic Compounds 5. iron (III) phosphate July 2, 201616 Fe 3+ PO 4 3- Fe 3 (PO 4 ) 3 FePO 4

17. Naming Polyatomic Compounds Don’t write name of the positive ion first followed by the name of the negative ion Examples: 1.LiOH 2.(NH 4 ) 2 SO 4 3.NaHCO 3 4. Fe(NO 3 ) 2 July 2, 201617 lithium hydroxide ammonium sulfate sodium bicarbonate iron(II) nitrate

18. Acids acid: a solution that contains H + (hydrogen ions) example: HCl - hydrogen chloride (white powder) when dissolved in water, the H + ion separates from the Cl - HCl (aq) – hydrochloric acid aqueous (dissolved in water i.e. in solution) July 2, 201618

19. Oxyacids oxyionoxyacid nameformulanameformula NO 3 - nitric acid ClO 3 - chloric acid CO 3 2- carbonic acid SO 4 2- sulfuric acid PO 4 3- phosphoric acid July 2, 201619 Note: the charge on the oxyion, indicates the number of H ions in the acid nitrate chlorate carbonate sulfate phosphate HNO 3 HClO 3 H 2 CO 3 H 2 SO 4 H 3 PO 4 oxyacids: acids formed when H + combine with polyatomic ions that contain oxygen (oxyions)

20. Homework Page 150 number 9 fghij, 10 e Page 151 number 5a, 6bd, 7ab Page 174 number 9fg, 10cdg Complete `Polyatomic Compounds Worksheet` July 2, 201620