Coordinate Covalent bonds (1 Viewer)

[-::Sanni::-]

How can you tell when a compound has a coordinate covalent bond?

I know some of those compounds (ammonium ion, hydronium ion?). Are there any others that you guys know?

 

[SkimDawg]

ozone has a coordinate covalent bond. Generally, A coordinate covalent bond is a convalent bond in which both of the shared electrons came from the one atom. Others include, carbon monoxide, and the ones you said.

 

[danz90]

Coordinate Covalent is when only ONE of the bonded atoms provides BOTH electrons for the covalent bond. For example, in Ozone. The central oxygen provides both electrons for the covalent bond. This results in an unpaired electron in one of the oxygens, thus making Ozone polar (because of the bent resonance structure).

With normal covalent bonds, there is usually one electron from one atom, and then another from the adjacent atom (in a single covalent bond).

Hope that makes sense lol

 

[Trebla]

How can you tell when a compound has a coordinate covalent bond?

I know some of those compounds (ammonium ion, hydronium ion?). Are there any others that you guys know?

At HSC level, it's usually pretty hard to tell. You have to know the mechanism of how the molecule is formed to know if a covalent bond exists.
However, in a general way, a molecule that has its valence electrons satisfied by the octet rule usually won't covalently bond any further, so an external atom which seeks a pair of electrons will usually form a coordinate covalent bond with it. You can also work it out by trial and error through electron accounting and the octet rule.

 

[-::Sanni::-]

Thanks SkimDawg, danz90 and Trebla! It's a bit more clear now!

 

[-::Sanni::-]

However, in a general way, a molecule that has its valence electrons satisfied by the octet rule usually won't covalently bond any further, so an external atom which seeks a pair of electrons will usually form a coordinate covalent bond with it.

Wait a second...is it possible for a noble gas to be involved in a coordinate covalent bond? The group's outer shell is filled up right, i.e. 8 electrons floating around?

 

[Trebla]

Wait a second...is it possible for a noble gas to be involved in a coordinate covalent bond? The group's outer shell is filled up right, i.e. 8 electrons floating around?

No, they don't under normal conditions. Though mind you, there have been noble gas compounds that have been created, so perhaps some of them might show coordinate covalent bonds.