Boron and aluminium are both found in group 3 of the modem periodic table. State what this tells you about the electronic configuration of both elements.
Explain what this tells you about the chemical properties of the two elements

Valence Electrons = 3

Explanation:

Not counting the transition metals, Boron and Aluminum are in group 3, but are actually in group 13. These elements usually have 3 valence electrons. Every element wants a full octet, or a full valence shell of eight electrons. It can do this by reacting with other elements through some bonds. Elements like these are not very reactive, especially in comparison to the alkali metals.

"among the transition metal elements, manganese and zinc have a slight lowering of electronegativities. the reason behind this is that the nuclear charges of these elements are slightly weaker than the other transition metal elements due to the way their valence electrons are filled up. both manganese and zinc have their valence electrons filled up to the 4th shell with 1 pair of electrons (4s2) completely occupying it. although the electrons in the 3rd shell (3d) are yet to be paired since the outer most shell is filled up, the ability of the nucleus to attract electrons is lessened. hence,   the electronegativity (or the ability to attract electrons) is lessened."

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