Periodic trends ionic formation

The metals of the s block of the Periodic Table have properties that can be interpreted in terms of the trend in their ionic radii down each periodic column. There is a very strong tendency towards formation of M+ (for ns1 or alkali) and M2+ (for ns2 or alkaline earth) metal ions, and other oxidation states are not important. With relatively high surface charge density, the alkali and alkaline earth metal ions are hard Lewis acids and have a preference for small hard Lewis bases. They particularly like O-donors, but can also accommodate N-donors, especially when present as part of a molecule offering a mixed 0,N-donor set. The number of metal-donor bonding interactions varies a great deal, depending in one... 

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