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How does electron transfer produce an ionic bond?

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Diagram showing four types of crystal bonding: ionic bonding with sodium and chlorine ions, covalent bonding with carbon atoms sharing electrons, metallic bonding with iron ions surrounded by free electrons, and molecular bonding with hydrogen molecules held by weak electrical attraction. — chemical bonding Different types of bonding in crystals.

An ionic bond is formed through the permanent transfer of valence electrons from one atom to another. This process typically occurs between atoms with a significant difference in electronegativity, often involving a metal and a nonmetal.12

The mechanism functions as follows:

Ion Formation: The atom that loses electrons becomes a positively charged cation, while the atom that gains these electrons becomes a negatively charged anion.12
Electrostatic Attraction: Once these oppositely charged ions are in close proximity, they are held together by strong electrostatic forces of attraction.12
Stability: This transfer allows atoms to achieve stable electron configurations, typically by filling their outermost electron shells.2

In an ionic compound, these ions arrange themselves into a lattice structure where the total number of electrons lost equals the total number gained, ensuring the substance maintains a net-zero charge.12