An ionic bond has a ___ electronegativity difference between atoms than a covalent bond and almost always involves ___.
smaller
An ionic bond has a larger electronegativity difference between atoms than a covalent bond and almost always involves the transfer of electrons.
To understand this, let's first explain electronegativity. Electronegativity is a measure of an atom's ability to attract electrons towards itself in a chemical bond. It is based on the number of protons in the atom's nucleus and its distance from the outermost electrons.
In a covalent bond, atoms share electrons to achieve a stable electron configuration. Covalent bonds generally form between atoms with similar electronegativities, meaning the electron density is shared more or less equally between them. This results in a neutral charge in the molecule or compound.
In an ionic bond, there is a large difference in electronegativity between the atoms involved. One atom has a significantly higher electronegativity than the other. As a result, the more electronegative atom attracts the valence electrons of the less electronegative atom more strongly. This leads to the transfer of one or more electrons from the less electronegative atom to the more electronegative atom. The atom that loses electrons becomes positively charged, called a cation, while the one that gains electrons becomes negatively charged, called an anion. The electrostatic attraction between oppositely charged ions forms the ionic bond.
In summary, an ionic bond occurs when there is a large electronegativity difference between atoms and it involves the transfer of electrons from one atom to another. This creates a bond between the resulting positively and negatively charged ions.