1. PART 3: Oxides and chorides of the third period (sodium  argon) adapted from Mrs. D. Dogancay

2. FormulaNa 2 OMgOAl 2 O 3 SiO 2 P 4 O 10 (P 4 O 6 ) SO 3 (SO 2 ) Cl 2 O 7 (Cl 2 O) State at 25°C Melting pt. (°C) Boiling pt. (°C) Electrical conductivity in molten state Structure Rxn w/ H 2 O Nature of oxide

3. FormulaNa 2 OMgOAl 2 O 3 SiO 2 P 4 O 10 (P 4 O 6 ) SO 3 (SO 2 ) Cl 2 O 7 (Cl 2 O) State at 25°C Melting pt. (°C) Boiling pt. (°C) Electrical conductivity in molten state Structure Rxn w/ H 2 O Nature of oxide solid (solid) solid (gas) liquid HHH H LLL - HH H LLL (gas) liquid

4. FormulaNa 2 OMgOAl 2 O 3 SiO 2 P 4 O 10 (P 4 O 6 ) SO 3 (SO 2 ) Cl 2 O 7 (Cl 2 O) State at 25°C Melting pt. (°C) Boiling pt. (°C) Electrical conductivity in molten state Good Very poor None Structure Rxn w/ H 2 O Nature of oxide solid (solid) solid (gas) liquid HHH H LLL - HH H LLL (gas) liquid

5. FormulaNa 2 OMgOAl 2 O 3 SiO 2 P 4 O 10 (P 4 O 6 ) SO 3 (SO 2 ) Cl 2 O 7 (Cl 2 O) State at 25°C Melting pt. (°C) Boiling pt. (°C) Electrical conductivity in molten state Structure Rxn w/ H 2 O Nature of oxide solid (solid) solid (gas) liquid H HH H LLL - HH H LLL (gas) liquid good none very poor ionic simple covalent molecular covalent macro- molecular

6. Physical properties - melting points, boiling points & conductivity: (from left  right) Left side of PT: oxides of Na, Mg and Al –ionic (metal + nonmetal… large difference in electronegativity) Ionic solids have high melting points Ionic solids are capable of conducting electricity in molten state (moving charge = electricity)

7. Physical properties - melting points, boiling points & conductivity: (from left  right) Middle of PT: oxide of Si (silicon dioxide) –macromolecular structure Strong diamond-like structure (covalently bonded network) accounts for high boiling point diamond SiO 2

8. Physical properties - melting points, boiling points & conductivity: (from left  right) Right side of PT: oxides of P, S and Cl –simple covalent molecules difference in electronegativities between element and oxygen is small low melting and boiling points

9. FormulaNa 2 OMgOAl 2 O 3 SiO 2 P 4 O 10 (P 4 O 6 ) SO 3 (SO 2 ) Cl 2 O 7 (Cl 2 O) State at 25°C Melting pt. (°C) Boiling pt. (°C) Electrical conductivity in molten state Structure Rxn w/ H 2 O Nature of oxide solid (liquid) solid (gas) liquid H HH H LLL - HHHLLL (gas) liquid good none very poor ionic simple covalent molecular Covalent network NaOH (aq),Mg(OH) 2(aq), does not react SO 3 forms H 2 SO 4 (aq) does not react basicacidic Amphoteric Reacts with base and acid

10. Chemical properties - Acid-base nature of oxides: (from left  right) Oxides of electropositive (opposite of electronegative) elements are very basic and form alkaline solutions. Na 2 O(s) + H 2 O(l)  MgO(s) + H 2 O(l)  NaOH(aq) 2 Mg(OH) 2 (aq)

11. Chemical properties - Acid-base nature of oxides: (from left  right) The amphoteric nature of aluminum oxide can be seen from its rxns w/ hydrochloric acid (a strong acid) and sodium hydroxide (a strong base) Acting as a base: Acting as an acid: omit Al 2 O 3 (aq) + 6HCl(aq)  2AlCl 3 (aq) + 3H 2 O(l)

12. Chemical properties - Acid-base nature of oxides: (from left  right) Silicon dioxide behaves as a weak acid. It does not react with water (that would be weird… SiO 2 is sand, so if sand chemically reacted with water then our beaches would be very different places). Imagine beach erosion rates if water chemically reacted with sand!!!

13. Chemical properties - Acid-base nature of oxides: (from left  right) The oxides of phosphorus, sulfur and chlorine are all strongly acidic (all form strong acids when added to water). SO 2 (g) + H 2 O(l)  SO 3 (g) + H 2 O(l)  H 2 SO 3 (aq) sulfurous acid H 2 SO 4 (aq) sulfuric acid

14. Chemical properties - Acid-base nature of oxides: (from left  right)