Ionic bond

[Sakshi]

Hey, i was going through the topic 'ionic bond' and read this- 

Quote

No bond is 100% ionic in character. It has some percentage of covalent character.

I didn't get the thing- how can an ionic bond be covalent? Please explain(with example). 

[studiot]

1 hour ago, Sakshi said:

Hey, i was going through the topic 'ionic bond' and read this- 

I didn't get the thing- how can an ionic bond be covalent? Please explain(with example). 

Hello and welcome Sakshi.

 

A better statement would be to say

No bond is 100% covalent in character. It has some percentage of ionic character.

 

You understand this you need to think about comparing covalent and ionic bonds.

Covalent bonds are all about sharing electrons.
Both molecules involved in the bond have an influence or share in the bonding electrons.
The actual bond is due to the lowering of electron energy that one or both bonding molecules experience as a result of the sharing as compared to not sharing.

Ionic bonds are all about transferring electrons.
The bond is due to the electrostatic forces between the newly created entities - the ions.

However these ions are not free to go on their travels.
As soon as that happens (eg in solution) there is no bond at all, although there electrostatic forces still operate.

So two bonded ions are not the same as two free ions.

The crystal structure and bond angles of a covalent material is governed by the disposition of the atomic orbitals of the parent molecules.
Water and diamond are good examples of this.
One important feature is that there are no free electrons kicking about so covalent materials are poor conductors of electricity at best. (Yes pure water is a poor conductor)

But in an ionic compound the crystal structure and bond angles are governed by electrostatic force laws between positive and negative entities.
This becomes a balance between like charges wanting maximum distance and the unlike ones wanting minimum distance apart.

However in answer to your original question the observed crystal structures and bond angles are rarely exactly as calculated from the above simplified principles.
The result shows some compromise between the two extremes.

The metallic bond fits in intermediate between these two extremes .