Question

Summarize HSAB theory?

Answer 1

Hard acids have affinity towards hard bases and soft acids have affinity towards soft bases.

Explanation:

One can characterize a base/acid as a hard or soft based on the following:

1) Hard acids and hard bases:
-have high electronegativity, high oxidation state and low polarization ability.

2) Soft acids and soft bases
-have low electronegativity, low oxidation state and high polarization ability.

List of hard/soft acids/bases can be seen here:
http://chemwiki.ucdavis.edu/Inorganic_Chemistry/Coordination_Chemistry/Hard_and_Soft_Acids_and_Bases