Electronegativity

what is electronegativity

the power of an atom to attract the pair of electrons in a covalent bond towards itself

the electron distribution between elements with different electronegativities will be ____________

assymetrical

what scale is used to assign a value of electronegativity for each atom

the pauling scale

what is the most electronegative element in the periodic table

fluorine, with a value of 4.0 on the Pauling Scale, its best at attracting electrons towards itself when covalently bonded to another atom

what are the 5 various factors affecting the electronegativity of an element

nuclear charge, atomic radius, shielding, position in a group, position in a period

how does nuclear charge affect the electronegativity of an atom

an increase in the no.protons leads to an increase in nuclear attraction for the electrons in outer shells

how does the atomic radius affect the electronegativity of an atom

electrons closer to the nucleus are more strongly attached towards its positive nucleus, the electrons further away from the nucleus are less strongly attracted towards the nucleus, therefore an increased atomic radius decreases electronegativity

how does shielding affect the electronegativity of an atom

filled energy levels can shield the effect of nuclear charge causing the outer electrons to be less attracted to the nucleus, therefore an increased no. inner shells and subshells will result in decreased electronegativity, across periods and down the groups of the periodic table, the electronegativity will vary

how does going down a group affect the electronegativity of an atom

there’s a decrease in electronegativity going down the group, the nuclear charge increases as more protons are added to the nucleus, however each element has a filled electron shell which increases shielding, the addition of extra shells increases the distance between the nucleus and outer electrons resulting in a larger atomic radii

overall there is a decrease in attraction between the nucleus and outer bonding electrons

how does going across a period affect the electronegativity of an atom

electronegativity increases across a period as the nuclear charge increases with addition of protons to the nucleus, shielding remains fairly constant due to no new shells being added to the atom and electrons go to the same outer shell, therefore the nucleus will have an increasingly strong attraction for the bonding pair of electrons of atoms across the period of the periodic table

why do atoms going across the periodic table have a smaller atomic radii

as the protons increase, electrons increase as well however shielding does not increase because the no.shells stays the same, because there are more protons, there is a stronger attraction between the nucleus and electrons, so all the electrons are pulled in closer to the nucleus

when two atoms in a covalent bond have the same electronegativity