What type of bond is formed by sharing two or more valence shell electrons between atoms?

The correct answer is covalent bond, as it specifically involves the sharing of two or more valence shell electrons between atoms to achieve stability. This type of bond typically occurs between nonmetal atoms, which have similar electronegativities. By sharing electrons, both atoms can fill their outer electron shells, leading to a more stable electronic configuration.

Covalent bonds can form single, double, or even triple bonds depending on how many pairs of electrons are shared between the atoms. For example, in a double bond, two pairs of electrons are shared, further contributing to the stability of the molecules formed. This sharing establishes a strong connection that is essential for the formation of various biological molecules, including proteins and nucleic acids.

In contrast, ionic bonds result from the transfer of electrons between atoms, leading to the formation of charged ions, while hydrogen bonds are weaker interactions that occur between molecules due to polar covalent bonds. Metallic bonds involve a delocalized sea of shared electrons among a lattice of metal atoms, which is distinct from the direct sharing characteristic of covalent bonds.