1. The oxides of elements in Period 3 L.O.:  Explain the physicals properties of the oxides in terms of their structure and bonding.  Describe the reactions of the oxides with water.

2. ElementNaMgAlSiPS Formulae of oxideNa 2 OMgOAl 2 O 3 SiO 2 P 4 O 10 SO 3 Structure of oxideIonic Mostly ionic Giant covalent Molecular covalent Melting point of oxide /°C 1275285220721703300-10

3. Ionic oxides contain the O 2- ion. This is a strongly basic ion which reacts with water to produce hydroxide ions: O 2- (aq) + H 2 O(l)  2OH - (aq) Thus all ionic oxides are BASIC.

4. ElementNaMgAlSiPS Formulae of oxides Na 2 OMgOAl 2 O 3 SiO 2 P 4 O 10 SO 2 SO 3 Acid-base character of oxide Basic Amph oteric Acidic pH of solution when dissolved in water 13 - 14107 (insolu ble) 7 (insolu ble) 0-12 – 3 (SO 2 ) 0-1 (SO 3 )

5. Exam questions (not Q5) Mark scheme