Lewis Structures & the Octet Rule - Theory & Examples

Lewis Structures - Theory & Examples

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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)

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