Understanding Octet Rule for NO2 and ClO-

  • Thread starter Thread starter a.a
  • Start date Start date
Click For Summary

Discussion Overview

The discussion revolves around the application of the octet rule to the molecules NO2 and ClO-. Participants explore whether these molecules adhere to the octet rule, with a focus on their structural representations and resonance forms.

Discussion Character

  • Debate/contested
  • Technical explanation
  • Conceptual clarification

Main Points Raised

  • Some participants question whether NO2 obeys the octet rule, noting that NO2+ does, but expressing uncertainty about the neutral NO2.
  • One participant suggests that NO2 exists as a resonance hybrid, where nitrogen typically forms three bonds and oxygens form two, implying a complex bonding scenario.
  • Another participant asserts that ClO- does obey the octet rule, comparing it to hydroxide (HO-) and suggesting that chlorine can achieve a complete octet with appropriate lone pairs.
  • A participant challenges the representation of bonds in NO2, questioning the idea of 'half bonds' and suggesting that additional bonding interactions between oxygen atoms might be necessary.
  • One participant claims that nitrogen in NO2 does not obey the octet rule, referencing its behavior in the liquid phase and discussing the stability of N2O4 as a related compound that does obey the rule.
  • There is a discussion about the nitrogen-nitrogen bond in N2O4, with participants clarifying that nitrogen typically forms three bonds and referencing other nitrogen compounds to support their points.

Areas of Agreement / Disagreement

Participants express differing views on whether NO2 and ClO- adhere to the octet rule, with no consensus reached. The discussion includes multiple competing interpretations of the bonding and structural characteristics of these molecules.

Contextual Notes

Participants mention various assumptions about bonding and resonance structures, and there are unresolved questions regarding the nature of bonds in NO2 and the implications for the octet rule.

a.a
Messages
126
Reaction score
0
Does NO2 obey the octet rule? I know NO2 + does so I figured that NO2 wouldn't I can't figure out how to draw NO2 using formal charges.

Does ClO- obey the rule? I tried drawing it and I think it does but I am not 100% sure
 
Physics news on Phys.org
NO2 obeys, but I'm not sure about ClO-, so I won't add to the confusion on that one.

NO2 exists as a resonance hybrid; that is, one double bond is shared between the two N-O bonds. Because of this, the oxygens get 2 bonds most of the time (making them neutral) while nitrogen gets 3 bonds most of the time (making it neutral). This picture shows the hybrid (the dotted lines imply sharing of the double bond):
http://en.wikipedia.org/wiki/Image:Nitrogen-dioxide-2D-dimensions.png"
 
Last edited by a moderator:
Cl-O- obeys the octet rule. You can think of it like HO-, aka hydroxide, except hydrogen has been replaced with chlorine. Then add lone pairs of course to make chlorine neutral and have a complete octet.
 
Nitrogen-dioxide-2D-dimensions.png


if the dotted lines represent 'half bonds' then the nitrogen would indeed have 3 bonds but each oxygen atom only has 1 1/2 bonds. shouldn't there be another dotted line between the 2 oxygen atoms?
 
No, the N in NO2 does not obey the octet rule (rules are there to be broken). Neither does N in NO. In the liquid phase (that is somewhere below 4 deg Celsius if I remember correctly). NO2 actually prevails as N2O4 which obeys the octet rule. The bond between the two N's is very weak, however. This is a general feature of the homopolar bonds at the end of the period. E.g., the bond in F2 is also very weak. The problem is that the elements at the end of the period are so crammed up with electrons, that electron repulsion couteracts bond formation.
 
280px-Stickstoffdioxid.svg.png


but the nitrogen always has 3 bonds. How could there be a N-N bond?
 
He's talking about the N-N bond in N2O4
 
so am I

ImagesHandler.ashx?id=23681.png

ImagesHandler.ashx?id=4574075.png
 
The upper of the two formulas is the one I am talking about.
Nitrogen does not form compounds with 3 bonds, only. Think of
The Ammonium ion NH_4+, Nitrylchloride NO_2Cl or Nitrylfluoride NO_2F.
 
Last edited:

Similar threads

  • · Replies 16 ·
Replies
16
Views
3K
Replies
33
Views
19K
  • · Replies 2 ·
Replies
2
Views
3K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 1 ·
Replies
1
Views
17K
  • · Replies 1 ·
Replies
1
Views
2K
Replies
1
Views
20K
  • · Replies 1 ·
Replies
1
Views
4K
  • · Replies 4 ·
Replies
4
Views
10K
  • · Replies 13 ·
Replies
13
Views
8K