Question

Every covalent bond has some ionic character and every ionic bond some covalent character. I can understand why a completely ionic bond is an ideal situation. But completely covalent bonds can exist(?). Take the case of H2

or any other diatomic molecule between identical atoms. How can these have any ionic character?

Answer 1

Completely covalent bonds can exist in certain situations, such as in diatomic molecules between identical atoms like H2. The ionic or covalent character of a bond depends on the electronegativity difference between the atoms involved.

Step-by-step explanation:

Covalent bonds occur when electrons are shared between atoms, and the degree of ionic or covalent character in a bond depends on the types of atoms involved. While all covalent bonds have some ionic character and vice versa, completely covalent bonds can exist in certain situations.

For example, in a diatomic molecule such as H2, the two hydrogen atoms are identical. Each hydrogen atom contributes one electron to form a shared electron pair, resulting in a purely covalent bond. Since the hydrogen atoms have the same electronegativity, there is no transfer of electrons and no ionic character in the bond.

Overall, the ionic or covalent character of a bond depends on the electronegativity difference between the atoms involved. If the difference is large, the bond will have more ionic character, whereas if the difference is small, the bond will have more covalent character.