Chemical bonding electrostatic potential maps

Understanding bond polarity is critical to understanding how organic reactions occur, because a central rule that governs the reactivity of organic compounds is that electron-rich atoms or molecules are attracted to electron-deficient atoms or molecules. Electrostatic potential maps (often simply called potential maps) are models that show how charge is distributed in the molecule under the map. Therefore, these maps show the kind of electrostatic attraction an atom or molecule has for another atom or molecule, so you can use them to predict chemical reactions. The potential maps for LiH, H2, and HF are shown below. 

But as the regions of high electron density above and below the plane of the ring in the electrostatic potential map (Figure 11.5) show, the tt electrons are less strongly held than the electrons in the C—H bonds. In Chapter 12 we will see how this fact governs the characteristic chemical reactivity of benzene and its relatives. 

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