To describe how a covalent bond forms. To use the octet dominance to covalent compounds

You have already seen examples of substances that contain covalent bonds. One substance discussed previously was water ((ceH2O)). You can tell native its formula that it is not an ionic compound; that is not written of a metal and a nonmetal. Consequently, its nature are different from those that ionic compounds.

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Electron Sharing

Previously, we discussed ionic bonding wherein electrons can be transferred from one atom to an additional so that both atoms have an energy-stable outer electron shell. Because most fill electron shells have eight electron in them, snucongo.orgists dubbed this tendency the octet rule. However, over there is another way an atom can achieve a complete valence shell: atoms deserve to share electrons.

This ide can be shown by using two hydrogen atoms, each of which has a solitary electron in the valence shell. (For small atoms such as hydrogen atoms, the valence covering will be the very first shell, i m sorry holds only two electrons.) We deserve to represent the 2 individual hydrogen atoms together follows:


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The Lewis diagram of 2 hydrogen atoms sharing electron looks prefer this:

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This depiction of molecules is simplified additional by making use of a dash to stand for a covalent bond. The hydrogen molecule is then stood for as follows:

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Each fluorine atom contributes one valence electron, making a solitary bond and also giving each atom a complete valence shell, i m sorry fulfills the octet rule:


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The circles present that each fluorine atom has eight electrons about it. Similar to hydrogen, we have the right to represent the fluorine molecule through a dash in place of the bonding electrons:


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In this molecule, the hydrogen atom walk not have actually nonbonding electrons, when the fluorine atom has actually six nonbonding electrons (three lone electron pairs). The circles present how the valence electron shells space filled for both atoms.


Example (PageIndex1)

Use Lewis diagrams to suggest the development of the following:

Cl2 HBr

Solution

a. When two chlorine atoms type a chlorine molecule, lock share one pair that electrons. In Cl2 molecule, every chlorine atom is surrounding by one octet number of electrons.

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The Lewis diagram for a Cl2 molecule is comparable to the one because that F2 (shown above).


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