Electronegativity and factors affecting electronegativity

Electronegativity:
The tendency of an atom to attract shared pair of electron towards it side is called electronegativity.

Variation of Electronegativity in group:
Electronegativity decrease from top to buttom in a group because as atomic size increase tendency to attract shared pair of electron decrease.

Variation of Electronegativity in periods:
Electronegativity increase from left to right in a period because as effective nuclear charge increase tendency to attract shared pair of electron increase.

Factors affecting electronegativity:

1.Oxidation state:
more is the oxidation state ,more is the attraction for electron, hence more will be the electronegativity. so pb^+4 is more electronegativity than pb^+2.

2 .Hyberdistaion:
Hyberdistation also affect electronegativity.
sp^3 25℅ s character
sp^2 33.3℅ s character
sp 50℅ s character

s orbital are more penetrating (s>p>d>f) so hybrid orbital with greater s character will be more electronegativity. so sp carbon atom is more electronegativity than sp^2 and sp^3 hybridisation of carbon atom.

4.Positive charge:
an atom with positive charge will attract electron more readily than a neutral atom .so positive charge atom are more electronegativity than neutral atom.

5.Bond order:
more is the bond order, more will be the electronegativity.

eg. carbon of alkyne is more electronegativity than carbon atom of alkene.

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