Lewis Structures & the Octet Rule - Theory & Examples | Chemistry Net

Lewis Structures & the Octet Rule - Theory & Examples

Lewis Structures - Theory & Examples

LEWIS STRUCTURES AND THE OCTET RULE - THEORY & EXAMPLES
PO4-3, PO3-, HO4P-2
P2H2, POCl3, IO3-
CH2N2, CN2H2, N2H3+, N3-
SO2Cl, HSO3Cl, S2O6
C2O4-2, BrO3-, N5+
CH3NO2, CH2NH, C2-2
CH3COOCH3, CH3CONH2, C3H4
C3H5+, C3H3N, BF

 

Lewis structures constitute an overwhelming majority of the structures that students encounter in courses in general chemistry, organic chemistry, or biochemistry. Hence, the writing of Lewis structures corresponding to a given molecular formula is an important exercise for them. The ability of students to write these structures correctly and then to calculate the formal charges of the atoms involved, is a prerequisite to understanding such topics as:

  • Resonance
  • Reactivity
  • Acidity and basicity
  • Bond and molecular polarities
  • Inter- and intra-molecular bonding
  • Isomerism and molecular geometry.

Since many chemistry textbooks do not give easy procedures for writing such structures an easy four-step method is presented and several worked-examples are given(1-3).

 


References

  1. G.N. Lewis, J.A.C.S, 38, 762-785, (1916)
  2.  E. C. McGoran, J. Chem. Educ., 68, 19-23 (1991)
  3. A.B.P. Lever, J. Chem. Educ., 49, 819-821, (1972)

3 comments:

  1. Quantum-mechanical aspects of the L. Pauling's resonance theory. http://vixra.org/pdf/1702.0333v1.pdf

    The L. Pauling's resonance theory analyzed using principle of quantum superposition, that is the principle of superposition "wave function", which is the main positive principle of quantum mechanics. The principle of quantum superposition is essentially a basic property of the wave function. By example of benzene molecule is shown that the principle of quantum superposition, and hence the quantum mechanics in general is in insurmountable conflict with the resonance theory.

    Quantum-mechanical aspects of the L. Pauling's resonance theory: http://vixra.org/pdf/1702.0333v1.pdf

    Bezverkhniy Volodymyr (viXra): http://vixra.org/author/bezverkhniy_volodymyr_dmytrovych

    Review. Benzene on the basis of the three-electron bond (full version). http://vixra.org/pdf/1612.0018v5.pdf

    Bezverkhniy Volodymyr (Scribd): https://www.scribd.com/user/289277020/Bezverkhniy-Volodymyr#

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    This screenshots (foto) (most with explanation) see by this link. Bezverkhniy Volodymyr (Archive.org): https://archive.org/details/@threeelectronbond

    Sincerely Bezverhny Volodymyr Dmitrievich.

    My ORCID iD: 0000-0002-3725-5571

    ReplyDelete
    Replies
    1. V. 2.
      Quantum-mechanical aspects of the L. Pauling's resonance theory.
      http://vixra.org/pdf/1702.0333v2.pdf

      Delete
  2. Quantum-mechanical analysis of the MO method and VB method from the position of PQS.
    http://vixra.org/pdf/1704.0068v1.pdf

    The MO method and the VB method are analyzed using the principle of quantum superposition (PQS) and the method of describing a quantum system consisting of several parts. It is shown that the main assumption of the molecular orbitals method (namely, that the molecular orbital can be represented like a linear combination of overlapping atomic orbitals) enters into an insurmountable contradiction with the principle of quantum superposition. It is also shown that the description of a quantum system consisting of several parts (adopted in quantum mechanics) actually prohibits ascribe in VB method to members of equation corresponding canonical structures.

    Using the quantum superposition principle, the MO method and the VB method were analyzed and it is shown that they are in contradiction with quantum mechanics. Also, using the quantum-mechanical description of a system consisting of several parts, it is shown that the attribution of canonical structures to the members of the equation is incorrect. Therefore, both the MO method and the VB method did not describe molecules with chemical bonds but actually, a lot of atoms (of which the described molecules consisted). That is, in the quantum chemical calculations, the chemical bond was "lost". Therefore, in order to "introduce" a chemical bond into calculations and avoid conflict with quantum mechanics, it is suggested to postulate the existence of MO as a new fundamental quality that describes a specific chemical bond and is not derived from simpler structural elements.

    Quantum-mechanical analysis of the MO method and VB method from the position of PQS:
    http://vixra.org/pdf/1704.0068v1.pdf

    ReplyDelete