The Partial Ionic Character of Polar Covalent Bonds

The Partial Ionic Character of Polar Covalent Bonds 

As we ve just seen, if you ask Is an X—Y bond ionic or covalent the answer in almost every case is Both, partially A better question is 7b what extent is the bond ionic or covalent The partial ionic character of a bond is related directly to the electronegativity difference (AEN), the difference between the EN values of the bonded atoms a greater AEN results in larger partial charges and a higher partial ionic character. Consider these three chlorine-containing molecules AEN for LiCl(g) is 3.0 - 1.0 = 2.0 for HCl(g), it is 3.0 - 2.1 = 0.9 and for CElg), it is 3.0 - 3.0 = 0. Thus, the bond in LiCl has more ionic character than the H—Cl bond, which has more than the Cl—Cl bond. 

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