Solve this:
Q.(c) What is electronegativity? Explain why halogens possess highest electronegativity.

Electronegativity is a measure of how strongly the nucleus of a given element attracts electrons toward itself. Fluorine is the most electronegative element in the periodic table.

In the case of halogen, there is no screening by inner electrons, it has many protons in its nucleus and because of the increasing positive charge of the nucleus electrons are attracted more and more strongly toward the nucleus.

These characteristics make it a highly electronegative element. Another thing we can see is that fluorine lies at the extreme upper right of the periodic table and the electronegativity increases as we move from the left to the right in any row of the periodic table.