Question

How do you find the electronegativity on the periodic table?

Answer 1

Electronegativity is the measure of the ability of an atom that is bonded to another atom to attract electrons to itself. Electronegativity increases across a period and decreases down a family.
$X(g)+{{e}^{-}}\to {{X}^{-}}(g)$

Complete step by step answer:
In a molecule, the tendency of the atom to attract a bonding pair towards itself is its electronegativity. $B$ is said to be more electronegative than $A$ if it pulls the bonding pair towards itself.
$(A)_{x}^{\bullet }(B)\to \overset{\delta +}{\mathop{(A)}}\,\overset{\delta -}{\mathop{(B)}}\,$
Variation in electronegativity in a group.
On moving down the group.
$Z$ increases but $Z^*$ remains constant
number of shells increases
atomic radius increases
force of attraction between added electrons decreases.
So here we can conclude that on moving down the group electronegativity decreases.
Variation in electronegativity in a period. Moving areas period from left to right.
$Z,Z^*$ increases
number of shells remain constant
en (atomic radius) decrease
force of attraction between added electrons increases
Hence electronegativity increases along the period.
Fluorine is the most electronegative element in periodic table

Note: The absolute value of electronegativity of an element cannot be determined but the relative value of electro negativity can be determined. The value of electronegativity also changes with the number of bonds formed between two elements. Higher the number of bonds between two atoms higher will be the electronegativity of an atom, so it is directly related with the number of bonds formed between two atoms.