Relative strength of Inorganic bases
(i) The basicity of a compound decreases with increase in electronegativity of the atom holding the electron pair,
(ii) The larger the size of the atom holding the unshared electrons, the lesser is the availability of electrons.
(iii) Presence of negative charge on the atom holding the electron pair increases the basicity, while the presence of positive charge on the atom holding the electron pair decreases the basicity.
(iv) Among alkali and alkaline earth hydroxides (oxides) the basic nature increases with electropositivity
is the strongest known base
(v) On going down the group; basic nature decreases with size of the central atom due to decrease in the ability to donate the lone pair.