Which of the following describes a covalent bond?

A covalent bond is defined by the sharing of electron pairs between atoms, allowing them to achieve a more stable electronic configuration. This type of bond occurs when two nonmetal atoms have similar electronegativities, which enables them to share electrons rather than completely transferring them, as seen in ionic bonds. By sharing electrons, the atoms can fill their outer electron shells, leading to increased stability for both.

The nature of this bond is crucial in the formation of molecules, as it results in the creation of structures that possess defined shapes and properties based on how the atoms are connected through these shared electrons. This sharing can occur in various ways, such as single, double, or even triple bonds, depending on how many electron pairs are shared between the atoms.

Understanding this fundamental concept of covalent bonding is vital in various fields of chemistry and biology, as it lays the foundation for understanding molecular structure and reactivity.