Covalent bonds length

FIGURE 2.21 Cov.ilent radii ot hydrogen and the p-block elements (in picometers). Where more than one value is given, the values refer to single, double, and triple bonds. Covalent radii tend to become smaller toward fluorine. A bond length is approximately the sum of the covalent radii of the two participating atoms. 

The covalent radius of an atom is the contribution it makes to the length of a covalent bond covalent radii are added together to estimate the lengths of bonds in molecules. 

The single bond covalent radius of carbon may be taken to be about 0.77 A, just half of the C—C bond length in diamond. Similarly, the covalent radii of chlorine and iodine may be set at 0.99 A and 1.33 A, respectively, one half of the interatomic distances in the Ch and I2 molecules. 

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