[appleseed]

ok , i know its a resonance structure but i thought of a way thats different
I have no idea how to insert a picture so ill try to describe it
Nitrogen in the centre
 bond between nitrogen and oxygen (electrons from N)
another dative bond between nitrogen and oxygen (electrons from N)
Finally, a single bond  and a dative bond (electrons from O)between the last oxygen and the center nitrogen

hmm ill try to insert an image


... do i insert the location of the file??

does it work?




ahaa attatch file!!

Thanks

[Vidya]

You can not have a dative and a bond with oxygen.You see in that doubly bonded Oxygen count the number of electrons around O .It has now 7 electrons,which is wrong.Oxygen has only 6 valence electrons .one electron it is sharing with N and two giving for dative bonding .4 as lone pairs ...so now count...

[cliverlong]

You can not have a dative and a bond with oxygen. << snip >>

If you mean it is not possible for there to be both a convential covalent bond (both electrons from both atoms) and also a dative/co-ordinate bond between two atoms then I believe that is incorrect.
See the entry about carbon monoxide here:
http://www.chemguide.co.uk/atoms/bonding/dative.html
and look at the bonding electrons between carbon and oxygen.

and here:
http://www.chm.bris.ac.uk/motm/co/coh.htm
Diatomic carbon monoxide has a triple bond between its atoms. One of the bonds forming the triple bond is a dative covalent bond.
Clive

[appleseed]

Thanks guys

( i sent a pm but not so sure it went through)
About the 7 electrons on the double bonded Oxygen. The Nitrate ion has a negative charge of 1-, so it has one extra electron. The red electrons shows the extra electron on NO3- that would would give it a negative charge.
Im still not so sure whether this is write or wrong. Ive searched on the web but there isnt the structure that i drew as another possibility

what do you think?


Thankyou!!!

[cliverlong]

Thanks guys

what do you think?

I think the bonding as described in the wiki entry
http://en.wikipedia.org/wiki/Nitrate
where the bonds between N and O are intermediate between "pure" double and "pure" single bonds is probably a reasonable simple model if you accept that the bonds are equal in distance and strength. This "bond equality" can't be accounted for if you take a simplistic view that bonds in a polyatomic ion or molecule must be solely due to the sharing of a pair of electrons localised betwen two atoms.
I believe (rather than think) that molecular orbital theory probably accounts better for this "bond equality" rather than drawing lots of "resonant structures" and then waving your hands around just to achieve a model of the bonds in nitrate composed of "pure single" or "pure double" character.

Clive

[appleseed]

Thanks guys

what do you think?

I think the bonding as described in the wiki entry
http://en.wikipedia.org/wiki/Nitrate
where the bonds between N and O are intermediate between "pure" double and "pure" single bonds is probably a reasonable simple model if you accept that the bonds are equal in distance and strength. This "bond equality" can't be accounted for if you take a simplistic view that bonds in a polyatomic ion or molecule must be solely due to the sharing of a pair of electrons localised betwen two atoms.
I believe (rather than think) that molecular orbital theory probably accounts better for this "bond equality" rather than drawing lots of "resonant structures" and then waving your hands around just to achieve a model of the bonds in nitrate composed of "pure single" or "pure double" character.

Clive

So is the structure i suggested wrong?

[Vidya]

Take care of formal charges and than decide about the structure.

[sm2345]

I think that if you think it in this way it would be clear:  The equal N-O bond lengths in NO3^- are due to the phenomenon of resonance. This ion has 3 resonating structures, and the resulting hybrid has all its bond lengths equal. Hence these N-O bonds have got partial double bond character. Also, it is trigonal planar due to sp2 hybridisation of N. Also, I think that there is an extra electron(apart from oxygen's own 6 & 1 from N) which gives it negative charge. In case of NO3- formation from HNO3, that electron comes from the acidic H atom. But there is no odd or unpaired electron in O atom in NO3- ion. The lp in Oxygen takes part in resonance.

[appleseed]

ok i understand that the resonance structure is the widely accepted, but im just asking whether the one i suggested is also correct?

yes?
No?

[sm2345]

Does "the one you suggested" mean the structure in the attached image?

[AWK]

From a formal point of viev (number of electrons, octets) all is formally OK
but compare:
http://www.mpcfaculty.net/mark_bishop/resonance.htm