Group IIIA metals valence electrons

There is also a pronounced tendency for the Group IIIA metals to form metal-metal bonds and bridged structures. The electron configuration ns2 np1 suggests the possible loss of one electron from the valence shell to leave the ns2 pair intact. The electron pair that remains in the valence shell is sometimes referred to as an inert pair, and a stable oxidation state that is less than the group number by two units is known as an inert pair effect. The fact that oxidation states of +2, +3, +4, and +5 occur for the elements in Groups IVA, VA, VIA, VIIA, respectively, shows that the effect is quite common. Thus, it will be seen that the Group IIIA metals other than aluminum have a tendency to form +1 compounds, especially thallium. 

The boron group (group 13 IIIA) consists of the elements boron (B), aluminum (Al), gallium (Ga), indium (In), and thallium (Ti). All have three electrons in their outer valence shell. A few exhibit metal-like characteristics by losing one or more of their outer electrons. For example, aluminum can lose one or three of its valence electrons and become a positive ion just as do other metals, but other elements in this group have characteristics more hke metalloids or semiconductors. 

Looking down the columns, groups IA and IIA have 1 and 2 valence electrons, respectively, in s orbitals. The transition metal families from left to right have 1 to 10 valence electrons, respectively, in d orbitals. Groups IIIA to VIIIA have 3 to 8 valence electron, respectively, in p orbitals. 

Aluminum, a chemically reactive metal in Group IIIA, has three valence electrons and forms a very stable 3+ ion. The ten electrons that remain in the Al3+ ion have the neon configuration. The other metals in Group IIIA behave similarly. 

Because boron is the only nonmetal with just three valence electrons at its disposal, it must resort to clever stratagems in its bonding and structure. All the other elements in Group 13 (Group IIIA) are metals their chemistries are reasonably straightforward and relatively... 

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