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6.15: Writing Lewis Structures for Molecules

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    49362
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    Because Lewis diagrams are widely used to describe the structures of molecules, it is important that you be able to construct them. The first step in this process is to draw a skeleton structure to show which atoms are linked to which. Next, determine how many valence electrons are available by adding the periodic group numbers for all atoms in the molecule. Finally, allocate the available electrons either as shared pairs or as lone pairs so that each atom has an octet (or in the case of H, a 1s2 pair).

    Deciding on a Skeleton Structure

    Multiple Bonds

    An Excess of Bonds

    Resonance


    This page titled 6.15: Writing Lewis Structures for Molecules was last modified on Thu, 20 Aug 2026 18:29:15 GMT and is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Ed Vitz, John W. Moore, Justin Shorb, Xavier Prat-Resina, Tim Wendorff, and Adam Hahn.

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