[Indranil (OP)]

Does Nitrite Ion make a co-ordinate bond with Oxygen with single covalent bond?

NO2.jpg (55.38 kB . 1371x776 - viewed 16488 times)

[chiralSPO]

Does Nitrite Ion make a co-ordinate bond with Oxygen with single covalent bond?

There are two equivalent resonance structures:

Screen Shot 2017-12-01 at 1.49.36 PM.png (13.88 kB . 558x206 - viewed 18183 times)

it can be depicted as:

Screen Shot 2017-12-01 at 1.51.42 PM.png (6.83 kB . 156x84 - viewed 12062 times)

and you can think of both N-O bonds being 1.5 bonds, halfway between single and double bonds.

[Indranil (OP)]

Does Nitrite Ion make a co-ordinate bond with Oxygen with single covalent bond?

There are two equivalent resonance structures:

Screen Shot 2017-12-01 at 1.49.36 PM.png (13.88 kB . 558x206 - viewed 18183 times)

it can be depicted as:

Screen Shot 2017-12-01 at 1.51.42 PM.png (6.83 kB . 156x84 - viewed 12062 times)

and you can think of both N-O bonds being 1.5 bonds, halfway between single and double bonds.

I don't understand what you mean. Could you get your points a little bit easier please?

[jeffreyH]

It appears to be straightforward. Since the double bond can be associated with either side you can obtain a symmetry by viewing it as 1.5 bonds at either side.

[Kryptid]

I don't understand what you mean. Could you get your points a little bit easier please?

He's saying that the electron dot structure you've posted is an oversimplification that is ultimately inaccurate. The nitrite ion does not consist of one N-O double bond and one N-O single bond. I'm guessing you haven't gotten to this point in chemistry class yet, but electrons in a double bond can sometimes spread over more than one bond. That is what is happening here. The electrons from the N-O double bond in the electron dot structure are actually spread equally over both of the N-O bonds.

[Indranil (OP)]

Does Nitrite Ion make a co-ordinate bond with Oxygen with single covalent bond?

But my question is that Does Nitrite Ion make a co-ordinate bond with Oxygen with single covalent bond? Still I am not clear. Could you clear please?

[chiralSPO]

I would say there are not any coordinate bonds in nitrite, only covalent. Both oxygen atoms are bound to the nitrogen atom in the same way. We can draw one with a double bond and one with a single bond, but it is more accurate to say both have 1.5 bonds.

[Indranil (OP)]

I would say there are not any coordinate bonds in nitrite, only covalent. Both oxygen atoms are bound to the nitrogen atom in the same way. We can draw one with a double bond and one with a single bond, but it is more accurate to say both have 1.5 bonds.

You are saying that there are not any coordinate bonds in nitrite, only covalent . But many books and sites show nitrite has a coordinate bond. I am confused. Could you explain please? Thanking you.

[chiralSPO]

Honestly, the distinction between a co-ordinate (dative) bond and a covalent one is mostly semantic. If you must learn it for a class, then you have to learn it, but I won't be able to help much because I haven't needed to care about that particular distinction in many years.

You could make a case that nitrate, NO₃^–, contains a dative bond, because one of the N–O bonds contains no "N-originated" electrons, as described here: https://chem.libretexts.org/Core/Physical_and_Theoretical_Chemistry/Chemical_Bonding/Fundamentals_of_Chemical_Bonding/Coordinate_(Dative_Covalent)_Bonding

But for nitrite, NO₂^–, we can say that 2 of the N valence electrons form the lone pair on N, and the three remaining valence electrons on N each make up half of the three N–O bonds.

The main problems I have with distinguishing between dative and covalent bonding is that it is confusing and not realistic. For instance, the website linked above describes the ammonium ion, NH₄⁺, as having three covalent N-H bonds, and one dative N-H bond, but we know from experimental data (NMR spectroscopy, IR spectroscopy, neutron diffraction, proton transfer kinetics etc.) that all N-H bonds in NH₄⁺ are identical. (same goes for borohydride, BH₄^–)

The problem only becomes worse when considering organoboron, organophosphorus and organometallic compounds. People can argue until they are blue in the face about which bonds are covalent and which are dative, but at the end of the day, the experiments show there is no reason to distinguish between the two.