Linked Questions
33 questions linked to/from What is resonance, and are resonance structures real?
3
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1answer
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How to explain (non-/anti-) aromaticity in fulvene with the help of resonance structures?
Can someone please explain why the resonance structures of fulvene 1 is non-aromatic and 2 is anti-aromatic?
Why is fulvene non-aromatic, even though it has $4\pi$-electrons and no $\mathrm{sp^3}$ ...
8
votes
3answers
7k views
Why does HNO2 not have resonance?
A question on the 1996 AP Chemistry Free Response asks:
The $\ce{N-O}$ bonds in the $\ce{NO2-}$ ion are equal in length, whereas they are unequal in $\ce{HNO2}$. Explain.
Since the nitrogen ...
5
votes
1answer
1k views
Where do the lone pairs go in the “true” resonance structure?
Consider the "true" resonance structure of $\ce{CO3^2-}$:
The bottom diagram leaves out the 2 lone pairs, so 4 electrons disappeared in the bottom image as compared to the top one. Are these ...
4
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1answer
906 views
VSEPR theory, chemical bond and quantum mechanics
VSEPR theory correctly predicts the shapes of many symmetry-broken molecules such as $\ce{H2O}$ and $\ce{NH3}$. Take $\ce{NH3}$ for example. In VSEPR theory, the nitrogen atom is (approximately) at ...
4
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1answer
1k views
How to determine the relative contribution of resonance structures when different rules give contradictory outcomes?
In order to determine the relative contributions of resonance structures, my textbook gives the following rules (in order):
The more covalent bonds a structure has, the higher it scores.
Structures ...
5
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2answers
464 views
What is the correct way to verify a structure's geometry, for example for benzene?
My goal is to compare a calculated bond length with experimental data. Benzene is obviously common enough to expect sufficient experimental data to be available for it on the internet.
I have found ...
3
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1answer
2k views
Which of the resonance structures is more stable?
I am quoting a rule on resonance from Organic Chemistry by T.W. Graham Solomons, Craig B. Fryhle, 12th edition, page 25.
Structures in which all the atoms have a complete valence shell of ...
6
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1answer
307 views
If I can't draw resonance structures for a pi system, does that mean it doesn't exist?
Whilst trying to answer this question I came across an interesting situation regarding the relationship between resonance structures and molecular orbitals. There are two places that you can ...
4
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1answer
333 views
Can a molecule be achiral whilst it's resonance form chiral?
I'm trying to work out whether methylphenylsulfoxide is a chiral molecule.
It is my understanding that the sulfur uses sp2 hybridised orbitals. Why is this? The central sulfur atom is bound to 3 ...
3
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1answer
102 views
How does resonance fail in approximating chemical structures?
In the book "Concise Inorganic Chemistry" by Prof. JD Lee, it says here:
These contributing structures do not actually exist. The $\ce{CO3^2-}$ does not consist of a mixture of these structures, ...
1
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1answer
174 views
Why does coumarin predominantly exist in keto form?
By applying the logic that phenol exists in enol form rather than keto form as it attains aromatic character, why is it not the case in coumarin?
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1answer
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Generalizations regarding functional groups on benzene ring
While studying several organic mechanisms (high school level), I came to an interesting generalization.
I claim that negative charge on phenoxide ion first ALWAYS delocalises onto the ring and then ...
0
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0answers
341 views
Which is most stable resonance structure of 4-nitrophenoxide ion?
According to my coaching module the first structure is more stable. Why is this so? I feel both must be approximately equally stable since negative charge is on oxygen in both cases. Would someone ...
3
votes
2answers
70 views
Why does delocalization (only) occur in molecules represented by resonance hybrids?
Before I start this question, I am aware tha
Electrons in all molecules are delocalized to some extent
Delocalization is a the phenomenon and resonance is an attempt to explain it.
When I asked this ...
-1
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1answer
208 views
Resonance structure and stability
Does the existence of resonance structures always translate as stability?
I've been taught that resonance structures generally "spread out" charge in order to compensate for deficiency or excess of ...