Question

How does the electronegativity of p-block elements change across a period?

Answer 1

Electronegativity:

• Electronegativity is the measure of the ability of an atom in a bond to attract electrons to itself.
• Towards the left of the table, valence shells are less than half full so these atoms tend to lose electrons and have low electronegativity.
• Towards the table’s right, valence shells are more than half full so these atoms tend to gain electrons and have high electronegativity.
• The electronegativity depends upon the size of the atom and the magnitude of the nuclear charge.
• Electronegativity increases with a decrease in the size of an atom and an increase in the magnitude of the nuclear charge.
• Thus, the atoms’ attraction for the valence electrons increases.

Electronegativity of p-block across a period:

• Electronegativity generally increases across a period in a periodic table and decreases as we move down a group.
• This is because across a period the nuclear charge increases faster than the electron shielding so the attracting power of atoms for the valence electrons increases.

Hence, in p-block elements Electronegativity generally increases across a period in a periodic table.