Final answer:
A nonpolar covalent bond forms between atoms of equal electronegativity, where atoms share electrons equally with no difference in electronegativity.
Step-by-step explanation:
The bond that can form between atoms of equal electronegativity is a nonpolar covalent bond. In such a bond, atoms share electrons equally because there is no difference in electronegativity between them, which is a measure of an atom's ability to attract electrons in a bond. An ionic bond involves the transfer of electrons from one atom to another, leading to the formation of ions. This occurs between atoms with a significant difference in electronegativity (generally considered to be greater than 1.9). A polar covalent bond occurs when atoms with different electronegativities share electrons unevenly, resulting in a molecule with a positive and a negative pole. Lastly, a metallic bond is a type of chemical bond found between atoms in metallic substances, involving the free floating of electrons among a lattice of metal cations.