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

You are watching: How many electrons are shared in a single bond

Ionic bonding commonly occurs once it is easy for one atom to shed one or much more electrons and another atom to gain one or much more electrons. However, part atoms won’t offer up or get electrons easily. However they still participate in compound formation. How? over there is an additional mechanism because that obtaining a finish valence shell: sharing electrons. Once electrons are shared between two atoms, they make a bond called a covalent bond.

Let us illustrate a covalent link by using H atoms, v the expertise that H atoms require only two electrons to to fill the 1s subshell. Each H atom starts v a single electron in that valence shell:

The 2 H atoms deserve to share their electrons:

We have the right to use circles to present that every H atom has two electrons around the nucleus, totally filling every atom’s valence shell:


Because each H atom has a to fill valence shell, this shortcut is stable, and also we have actually made a diatomic hydrogen molecule. (This explains why hydrogen is just one of the diatomic elements.) because that simplicity’s sake, the is not inexplicable to represent the covalent bond v a dash, rather of v two dots:


Because 2 atoms space sharing one pair that electrons, this covalent shortcut is referred to as a single bond. As one more example, take into consideration fluorine. F atoms have seven electron in their valence shell:


These 2 atoms deserve to do the same thing that the H atom did; they share your unpaired electron to do a covalent bond.

See more: Does It Hurt The First Time A Guy Fingers You Get Fingered? Does It Hurt The First Time You Get Fingered


Note the each F atom has actually a complete octet around it now:


We can likewise write this using a dash to represent the mutual electron pair:


There are two different varieties of electrons in the fluorine diatomic molecule. The bonding electron pair makes the covalent bond. Every F atom has three other pairs of electrons that perform not take part in the bonding; castle are called lone pair electrons. Every F atom has actually one bonding pair and three lone bag of electrons.

Covalent bonds can be made in between different facets as well. One instance is HF. Every atom starts out through an odd variety of electrons in that valence shell: