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Learn about the Stability of Resonating Structures

The stability of the resonating structure depends on the dispersal of charge and separation with opposite charges in the molecule. The stability of the molecular atom increases due to the number of electronegative atoms with a negative charge and electropositive atoms with a positive charge. The stability of the resonating structure causes the polarity in the molecule. The polarity of the molecules occurs due to the interaction of two 𝛑- bonds or a lone pair of electrons and a pi bond present in the atom in the adjacent position. 

Explain the Stability of Resonating Structure

The stability of the resonating structure refers to all atoms that have completed the valence shells and the atoms with a full octet. The structure with a minimum number of formal charges is more stable and the stability increases with the decreasing number of atoms in the molecule. The molecular structure with more electronegative atoms helps to create a negative charge and increases the stability of the atomic molecule. The least electronegative atom causes a positive charge that increases the stability of the molecular atom. The relative position of the positive and negative charges increases the stability of the molecular atoms.

The Least Stable Resonating Structure

The latest stable resonating structure refers to the atomic structure with negative charges on the carbon atom attached to the -NH2 group. This position of the atom donors frees electrons that destabilize the molecule. CH3+ the methyl carbonium ion is the least stable molecule due to the nature of free disperse of the molecular electrons. The least stable resonance impacts the resonance structure that helps in the movement of charge between two molecular atoms or more.

What are the Rules of Stability of Resonating Structures?

  • All the atoms in the structure must have completed valence shell to increase the stability of the molecule
  • A carbon atom that contains a positive charge has an incomplete octet therefore it is not stable
  • The least stable structure is less contributor to the condition of  hybrid resonance
  • The structure with a lower number of atoms with formal charges is more stable than the greater number of molecular atom
  • The structure must have a negative change on the strong electronegative atom to increase the stability 

Explain Stability of the Resonating Structure of Phenol

Phenol generally contains five resonating structures among them two structures are in Kekule form. The remaining structures are like charge separation which describes the stability of the molecular atom. The strong acidic nature of the phenol molecule has a partial positive charge due to the resonance. Phenol has the anion formed by the release of hydrogen ions and is also stable. The table resonating structure of phenol has the octet completed in the molecule. Phenol is generally an aromatic organic compound that has the molecular formula of C6H5OH. Phenol is a white crystal molecule that is volatile and the volatility changes due to the stability of the atoms in the resonance.

Explain the Effect of Resonance

The positive resonance effects occur due to the release of the electrons to the ether molecules and by the process of delocalization. The examples of the stable positive resonance effects are -OR,-OH,-SR, and -SR. The effect of the positive resonance causes polarity in the molecules due to the interaction of the lone pair of electrons and two pi bonds in the molecule. Molecules with the conjugated double bond show the effects of resonance. On the other hand, the molecule with a single pair of electrons and a single double bond has the resonance effects and stable structure of resonance.

Resonating Structure of Phenol

In the resonating structure of phenol, the OH group becomes strongly activated and increases the density of the electrons on benzene. The strong electron density makes the atomic structure of phenol full of electrons. Hence due to the electron risk, the resonance structure of phenol readily releases electrons to the oxidizing agents. However, the nitration process of phenol is the electrophilic substitution. 


The above study indicates that the stability of the resonating structure increases with the decrease in the molecular atoms and helps to create more electronegativity in the negative charge. The study also indicates that the polarity of the strong resonance molecules depends on the release of free electrons from the molecules. The article also illustrates that the phenol has a stable structure of resonance as the ring of the phenol is electron-rich and easily releases free electrons to the oxidizing agent. 


Frequently asked questions

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What are the conditions for the stable resonance structure?

Ans. The resonance structure should contain the same atomic number and the same number of unpaired electrons. The St...Read full

What is the stability in resonance form?

Ans. Resonance helps in the delocalization of the structure and the total energy of the structure decreases. The sta...Read full

What are the primary rules of resonance?

Ans. The primary rules of resonance suggest that all the structures of resonance should have the least atom in the m...Read full

What is meant by the positive resonance?

Ans. The positive resonance effect refers to the process of delocalization and the release of free electrons for inc...Read full