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Chemistry Periodicity 9.2 and 9.3 - Coggle Diagram

- - - - Magnesium also reacts vigorously, so does powdered aluminum (no oxide layer). Burns with white flames.
        2Mg(s) + O2(g) ---> 2MgO(s)
        4Al(s) + 3O2(g) ---> 2Al2O3(s) [The only amphoteric and both ionic and covalent characteristic]
      - Silicon reacts slow. Si(s) + O2(g) --> SiO2(s)
      - Sodium reacts vigorously and forms a bright yellow flame when heated with oxygen to form white sodium oxide. 4Na(s) + O2(g) ---> 2Na2O(s)
      - Phosphorus reacts vigorously with yellow/white flames.
        4P(s) + 5O2(g) ---> P4O10(s)
      - Sulfur powder, once ignited, burns gently with a blue flame.
        S(s) + O2(g) ---> SO2(g) [Oxidation state +4]
        Can form trioxide in a REVERSIBLE reaction with vanadium oxide catalyst.
        2SO2(g) + O2(g) ----> 2SO3(g) [Oxidation state now +6]
      - Oxides reaction as base or acid. https://chemistryguru.com.sg/period-3-oxide-reaction-water-acid-base
        
        Oxide reaction with base and/or acid.
        https://www.savemyexams.com/a-level/chemistry/cie/22/revision-notes/2-inorganic-chemistry/2-1-the-periodic-table-chemical-periodicity/2-1-4-period-3-oxides--hydroxides-acidbase-behaviour/
      - As the elements become more electronegative, the bonds become more covalent and hence it shifts from giant ionic to simple molecular. Hence the reactions of these with water become more vigorous as the molecules are weaker.
    - - Sodium, Magnesium, and Aluminium plunged into gas jar, VIGOROUS reaction.
        2Na (s) + Cl2 (g) ---> 2NaCl (ionic)
        Mg (s) + Cl2 (g) ---> MgCl2 (ionic)
        2Al (s) + 3Cl2 (g) ----> Al2Cl6 (ionic and covalent, giant covalent)
      - Silicon reacts slowly with chlorine. Si(s) + 2Cl2(g) ---> SiCl4(l) [simple covalent, covalent bonding]
      - Phosphorus and sulfur reacts slowly with EXCESS chlorine. They become simple molecular, covalent.
        2P(s) + 5Cl2(g) ---> 2PCl5(l)
      - Argon doesn't react.
    - - SLOW reaction unless heated.
        Mg (s) + 2H2O (l) ---> Mg(OH)2 (aq) + H2 (g)
      - With chlorides of Period 3 elements, Na and Mg dissolves whilst the others form increasingly acidic solutions by reacting and giving HCl gas.
        
        likely pH
        
        NaCl - 7
        
        MgCl2 - 6.5
        
        Both cause polar water molecules to be attracted to it and hence it dissolves to become hydrated ions.
        
        Al2Cl6 - 3
        
        Al2Cl6 is both ionic (AlCl3) and covalent. When Al is hydrated, it causes water to lose a hydrogen ion which makes the solution acidic as it forms HCl gas.
        
        SiCl4 - 2
        
        PCl5 - 2
        
        Forms both phosphoric acid and hydrochloric acid.
        
        SCl4 - 2
      - VIGOROUS reaction with water.
        2Na (s) + 2H2O (l) ---> 2NaOH (aq) + H2 (g)
        
        NaOH(aq) + HCl(aq) ---> NaCl(aq) + H2O(l)
        Mg(OH)2(s) + 2HCl(aq) ---> MgCl2(aq) + 2H2O(l)
        Al(OH)3(s) + 3HCl(aq) --->AlCl3(s) + 3H2O(l)
      - Al(OH)3 is amphoteric
        
        Al(OH)3(s) + NaOH(aq) ----> NaAl(OH)4(aq)
- - - - You can predict its physical and chemical properties.
    - - Compare to other elements in the same group
- - - - Metallic bonding and structure, free electrons.
        Al has the most valence electrons so it is the strongest and best conductor.
    - - Covalent, simple molecular
        
        Weak id-id forces holding them together
    - - Giant covalent, macromolecular
        
        Only a semi-conductor since it has giant covalent but no free electrons so it is a poor conductor.