Explain 03 CO3 -2?

On 8/23/2025 at 1:05 PM, HbWhi5F said:

This O3 Lewis Diagram looks weird -

why does atom with 8 electrons positive,

why is atom with 4 electrons neutral,

why is atom with 6 electrons negative

In CO3 -2 Why there is a -2 charge ?

What is happening in HNO3 ?

N is positive that means it is 5 electrons short of Nobel config.

Why there is a negative charge on bottom oxygen ?

Are these Lewis Diagram possible or covalent and electrovalent bonds ?

[NO2]-

is there 1 electron extra on oxygen ?

[NO2]-

While this has already been adequately covered by others, I think one concept that could help understanding is what used to be called in my day "dative" bonds. These are bonds in which both electrons can be thought of as coming from only one of the two atoms, instead of the more standard idea of one from each. Dative bonds were shown by an arrow, e.g. O=O->O indicating from which atom the 2 electrons notionally come. Thus for your ozone diagram, the central atom donates one of its lone pairs to share with the oxygen on the right, thereby completing its octet, but at the expense of acquiring a +ve charge, because both electrons would need to stay on the central atom if it were to remain electrically neutral. This charge separation (polarisation) is observed experimentally, by the way, so it is real. The second idea is the notion of so-called "resonance hybrids". This is the idea that as the single bond can just as well be on the left as on the right, the bonding in the molecule will actually be a mixture of the left and right options, with one and a half bonds to each and half a -ve charge on both the outer oxygen atoms. (You may know that the bonding of benzene is likewise a mixture of the 2 Kekulé bonding schemes with alternate single and double bonds, the real molecule having one and a half bonds between all atoms, indistinguishably.) The term "resonance" hybrid is now out of favour as there is no physical "resonance": it's just a static mixture of the 2 bonding options.

If you do the bonding with "proper" quantum mechanics, using the "molecular orbital" method, you get exactly the same result, viz. an electron density across the molecule that corresponds to a "mixture" of the two structures. So it's an easy way to represent the bonding that gives the right answer, most of the time at least, without getting into MO theory.

The same thing happens with a number of the other structures in your list. I confess I don't know what terminology is used in education today for these ideas. I would avoid "resonance " I think, as that is potentially misleading, and just speak about structures being a mixture of the two.

Edited August 27Aug 27 by exchemist