Lewis Structures & the Octet Rule - Theory & Examples

LEWIS STRUCTURES AND THE OCTET RULE - THEORY & EXAMPLES

SO2, SO3, SO3-2, SO4-2	Lewis Structures & the Octet Rule	H2CO3, CO, CO2, CO3-2
SCN-, OCN-, NCN-2	HCN, CN+, CN-, O3	COCl2, CS2, HNCHNH2
NO, NO2, NO2+, NO2-	NO3-, HNO3, NOCl	N2O, N2O3, N2O4, N2O2
N2F+, CF3NO, HO2NO2	HClO3, HClO4, Cl2O4	ClO2, ClO2+
Cr2O7-2 , CrO4-2 , CrO3, H2CrO4	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	Lewis Structures	Lewis Structures
Lewis Structures	Lewis Structures	Lewis Structures

 

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).

 

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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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