From the periodic table, the number of valence electrons for most of the main group elements may be determined directly from the from the periodic table, the number of valence electrons for most of the main group elements may be determined directly from the atomic number. group number. period number. nucleon number.

The number of valence electrons for most of the main group elements may be determined directly from the group number

First we will define what is meant by valence electrons.

Valence electrons are those electrons that reside in the outermost shell surrounding an atomic nucleus.

Hence, the number of valence electrons for most of the main group elements may be determined directly from the group number.

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You can determine the number of valence electrons (VE) for main group elements directly from the Group number.

For the s-block, VE = Group No.

For the p-block, VE = Group No. - 10

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