define covalent bond. Show covalent bond formation with Lewis electron period diagrams.

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Ionic bonding typically occurs when it is easy for one atom to shed one or more electrons and another atom to get one or much more electrons. However, some atoms won’t give up or gain electrons easily. However they still get involved in link formation. How? there is one more mechanism because that obtaining a complete valence shell: sharing electrons. Once electrons are shared in between two atoms, they do a bond called a covalent bond.

Let us show a covalent shortcut by making use of H atoms, through the expertise that H atoms require only 2 electrons to fill the 1s subshell. Each H atom starts v a solitary electron in the valence shell:

\<\mathbfH\, \cdot \; \; \; \; \; \mathbf\cdot \: H\>

The two H atoms have the right to share your electrons:

\<\mathbfH\: \mathbf: H\>

We have the right to use one to show that each H atom has two electrons about the nucleus, completely filling every atom’s valence shell:


Because each H atom has a filled valence shell, this link is stable, and also we have actually made a diatomic hydrogen molecule. (This defines why hydrogen is just one of the diatomic elements.) because that simplicity’s sake, it is not unexplained to stand for the covalent bond through a dash, instead of through two dots:


Because two atoms are sharing one pair of electrons, this covalent bond is called a single bond. As another example, think about fluorine. F atoms have seven electron in your valence shell:


These 2 atoms deserve to do the exact same thing the the H atom did; castle share their unpaired electron to make a covalent bond.

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Note that each F atom has actually a finish octet approximately it now:


We can additionally write this utilizing a dash to stand for the common electron pair:


There are two different varieties of electrons in the fluorine diatomic molecule. The bonding electron pair makes the covalent bond. Each F atom has three various other pairs of electrons that carry out not get involved in the bonding; lock are dubbed lone pair electrons. Every F atom has actually one bonding pair and also three lone bag of electrons.

Covalent bonds deserve to be made in between different facets as well. One instance is HF. Each atom beginning out through an odd number of electrons in that valence shell: