Redox properties

The oxidation states for the Group
elements are given below. Examples are given of species in each of the oxidation states.
The most stable state for each of the elements is marked with an asterisk.
 
  • The most stable state is the most reluctant reactant in redox reactions.
    Thus for all Group
    elements other than lead, the +4 state is a weak oxidant.

     

  • States above the most stable state are good oxidants.
    Thus Pb(+4) is a good oxidant.

     

  • States below the most stable state are good reductants.
    Thus CO, CH4 and Sn(+2) are good reductants.
     
    CSiGeSnPb
    +4*
    CO2,CCl4    		+4*
    SiO2,SiCl4    		+4*
    GeO2, GeCl4    		+4*
    SnO2, SnCl4    		+4
    PbO2, PbCl4
    +2
    CO    		 +2
    GeO, GeCl2    		+2
    SnO, Sn2+    		+2*
    PbO, PbCl2
    0
    C    		0
    (Si)    		0
    Ge    		0
    Sn    		0
    Pb
    -4
    CH4    		    
Dr Sheila Woodgate
© The University of Auckland 2002