To explain how a covalent shortcut forms. To use the octet preeminence to covalent compounds

You have already seen examples of substances that contain covalent bonds. One substance pointed out previously was water ((ceH2O)). You deserve to tell indigenous its formula the it is no an ionic compound; that is not written of a metal and a nonmetal. Consequently, its properties are various from those the ionic compounds.

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Electron Sharing

Previously, we debated ionic bonding whereby electrons have the right to be transferred from one atom to an additional so the both atoms have actually an energy-stable outer electron shell. Since most to fill electron shells have eight electron in them, cg-tower.comists called this propensity the octet rule. However, there is another way an atom can accomplish a full valence shell: atoms deserve to share electrons.

This concept can be portrayed by using 2 hydrogen atoms, every of which has a solitary electron in that valence shell. (For tiny atoms such as hydrogen atoms, the valence covering will it is in the very first shell, which holds just two electrons.) We deserve to represent the 2 individual hydrogen atoms together follows:


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The Lewis diagram of two hydrogen atoms sharing electron looks favor this:

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This explicate of molecule is simplified further by utilizing a dash to stand for a covalent bond. The hydrogen molecule is then represented as follows:

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


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The circles show that every fluorine atom has eight electrons approximately it. As with hydrogen, we deserve to represent the fluorine molecule v a dash in ar of the bonding electrons:


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In this molecule, the hydrogen atom does not have nonbonding electrons, while the fluorine atom has six nonbonding electrons (three lone electron pairs). The circles display how the valence electron shells room filled because that both atoms.

See more: Forming Ions Form When Atoms Gain Or Lose, Forming Ions


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b. Once a hydrogen atom and also a bromine atom form HBr, they share one pair that electrons. In the HBr molecule, H achieves a complete valence of two electrons (duet) while Br achieves an octet. The Lewis diagram for HBr is comparable to that for HF displayed above.

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