Final answer:
A chemical bond formed when two atoms share electrons is called a covalent bond.
Step-by-step explanation:
The chemical bond that is formed when two atoms share electrons is called a covalent bond. Atoms engage in chemical bonding to achieve a full outer energy level or valence shell, which provides the most stable electron arrangement. Unlike ionic bonds, where electrons are transferred entirely from one atom to another, in covalent bonding each atom contributes one electron to the shared pair, forming a molecule. This can be represented in a Lewis structure, which uses dots to indicate valence electrons and lines to represent shared pairs of electrons. For example, in an H-Cl molecule, the hydrogen and chlorine atoms share a pair of electrons, with chlorine also having three lone pairs of unshared electrons.