Effect of Nonbonding Electrons and Multiple Bonds on Bond Angles

Effect of Nonbonding Electrons and Multiple Bonds on Bond Angles 

We can refine the VSEPR model to explain slight distortions from the ideal geometries summarized in Table 9.2. For example, consider methane (CH4), ammonia (NH3), and water (H2O). All three have a tetrahedral electron-domain geometry, but their bond angles differ slightly  

Because multiple bonds contain a higher electronic-charge density than single bonds, multiple bonds also represent enlarged electron domains. Consider the Lewis structure of phosgene  

Because three electron domains surround the central atom, we might expect a trigonal-planar geometry with 120° bond angles. The double bond, however, seems to act much like a nonbonding pair of electrons, reducing the Cl— C— Cl bond angle to 111.4°  

In general, electron domains for multiple bonds exert a greater repulsive force on adjacent electron domains than do electron domains for single bonds. 

Why is the voiume occupied by the nonbonding eiectron pair domain iarger than the voiume occupied by the bonding domain  

What is the bond angle formed by an axial atom, the central atom, and any equatorial atom  

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