Question

Compare and contrast the chemistry of group 1 metals with that of group 2 metals with respect to the following:

Polarizing power of cations increases on going from group 1 to group 2.

Answer 1

Ionic radius increases down the group reducing the polarizing power of the cation.group 2 metal are less stable than group 1 because they have a smaller ionic radius .

The polarizing power and polarizability which enhances the formation of covalent bonds is favoured by the following factors:

Small cation: the high polarizing power stems from the greater concentration of positive charge on a small area. This explains why LiBr is more covalent than KBr.

Large anion: the high polarizability stems from the larger size where the outer electrons are more loosely held and can be more easily distorted by the cation. This explains why for the common halides, iodides, are the most covalent in nature .