It is also an important Periodic Table of elements property. The Electronegativity (EN) tells a lot of characteristics of an element and it also important criteria in formation of molecules.
In previous post, you have learn about Atomic size/Atomic Radius of Atom. But Now we are going to see about an element makes bond with another element, its other qualities are surfaced and it behaves differently in response to the changed Environment
Electronegativity :- ( Explanation )
Like when child interacts with another child for the very first time, his personality and character is explored, Either he dominate others or is dominated by others or may be a equality also possible.
Similarly when an element makes bond with other element, its hidden qualities and characteristics are appear. Electronegativity ( EN ) is one the hidden qualities.
Whenever two atoms makes bond with each other they share bonding electrons but there is always an fight for those bonding electrons to getting greater share of electrons.
Each of the atoms are tries to pull the bonding electron to its nearby, to get major share.
It is a format of game of strength whichever has higher strength to pull the bonding electrons, win the game and has greater share of bonding electrons. That strength is known as Electronegativity (EN).
|Hcl – Electronegativity|
Definition :- ( Electronegativity )
Electronegativity (EN) is a tendency of an atom or element to pull bonding electron towards itself.
As in case of water Molecule, Oxygen pulls the bonding electron towards itself.
|HI – Electronegativity|
Electronegativity (EN) : (Across the Group)
When going down the group, the number of protons are increases which makes the nuclear charge stronger. But size of the atom is increasing down the group so the distance between nucleus and bonding electron is higher. So the attraction of bonding electron by nucleus is less.So Electronegativity (EN) decreases by going down the group (column).
Electronegativity (EN) : (Across the Period)
When going left to right across the period,size of the atom/element is decreased but also increase in the number of protons that makes stronger nuclear charge.As the number of orbits are remains same,it gets easy for nucleus to attract the bonding electrons.So Electronegativity (EN) Increases by across the period (Left to Right)
Factors affecting Electronegativity (EN) :-
In 1930, Scientist Pauling discribed the Electronegativity as the tendency of an atom or element to attract the bonding electrons in the molecule.The factors affecting Electronegativity (EN) are
|NaF – Electronegativity|
• Size of an Atom :-
In the smaller atom orbits are arranged closely to the Nucleus as compared to the larger atom. So the Nucleus can attract the bonding electrons effectively. So the Smaller the size of atom larger will be the Electronegativity.
• Shileding effect :-
How Effectively the inner sub-shells shield the outer electrons(Shielding Effect).Stronger the shielding effect means the nucleus attraction is of Electrons is less, weaker the shielding effect means the nucleus can attract the electron and bonding electron also.
• Nuclear Charge :-
Higher the nuclear charge, it can attract the bonding electron effectively.
• Electronic Configurations :-
Full-filled and Half-filled sub-shells have extra stability. Elements nearing the Half-filled and Full-filled sub-shell has higher desire to get attract the bonding electrons so that they can achieve stable Configurations
Unit of Electronegativity :-
Electronegativity is relative quality so it has no units. The Electronegativity values we’re referring today is discovered by Pauling.
According to Pauling scale of Electronegativity, The Group 1 ( Alkali Metals ) has lowest Electronegativity and Group 17 ( Halogens ) has Highest Electronegativity.
Electronegativity is also plays an important role in deciding the nature of bond.
I hope this useful,