Question

What trend in electronegativity do you see as you go across a period/row on the periodic table?

Answer 1

Electronegativity is the measure of the tendency of an atom to attract a shared pair of electrons towards itself. We can find the difference in electronegativity by subtracting the greater by the smaller one.

Complete step by step answer:
A lot of factors such as nuclear charge, number of electrons, location of electrons, the number of shells, etc. determine the electronegativity of an atom.
More the electronegativity of an atom more strongly the element attracts the shared pair of electrons and vice versa that more strongly an atom is being shared by an element more it’s electronegativity.
Electronegativity increases from top to bottom in a group because the number of shells increases as we go down.
Electronegativity also increases as we go from left to right in a period because there is an increase in a number of atoms as we move towards the left.
By this we can say that Fluorine is the most electronegative element and francium is the least electronegative element (refer to periodic table for convenience).
Also we know the noble gases helium, neon, and argon are not placed in Pauling electronegativity scale since they are inert and have fully filled orbitals.
The difference in electronegativity between atoms determines the type of bond they will form.

Note: Most of these trends are smooth for the main group elements but not among transition metals and inner transition metals. Also, exceptions are always there because of difference in origin, composition of different elements.