The Gordy Electronegativity Scale

Gordy s electronegativity differences are very nearly proportional to Pauling s (0.62 Gordy unit per Pauling unit) the two scales become almost identical if 0.80 is added to each of Gordy s values  

Moreover, Gordy s electronegativity differences are proportional to those on the Mulliken scale also. 

It is interesting that the three different criteria that we have considered give us electronegativity scales that are very similar. This indicates that, despite the difficulty in defining it, the concept of electronegativity is a meaningful one. 

In Chapter 3, it was pointed out that a double bond (often referred to as a bond of bond number 2) between two atoms is shorter than a single bond (bond number 1) between the same two atoms triple bonds are still shorter than double bonds. 

In discussing the resonance concept (p. 54), which allows a molecule to be represented by two or more structures, it was seen that a bond represented as a single bond in one of the structures might well be represented as double bond in another structure. In benzene (one of the simplest cases) the three carbon-carbon double bonds in one Kekule structure become single bonds in the other. The bond number here is between 1 and 2, but a more exact specification of bond number would depend on how this number is described, and agreement is by no means universal on this point. Since, however, the two Kekule structures of benzene are equivalent, it is quite reasonable to assign a number of 1.5 to the carbon-carbon bonds. Similarly, for the carbonate ion, 

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