Electrons are not bonded themselves; rather, electrons, specifically valence electrons, facilitate the bonding between atoms. This bonding arises from the electrostatic attraction between positively charged atomic nuclei and the negatively charged electrons of other atoms.
Here's a breakdown of how electrons are involved in forming chemical bonds:
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Valence Electrons are Key: Only the valence electrons (the electrons in the outermost shell of an atom) participate in bonding.
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Electrostatic Attraction: Each atom's nucleus attracts the valence electrons of other nearby atoms. This attraction is the primary driving force behind chemical bond formation.
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Sharing or Transferring Electrons: Atoms bond to achieve a stable electron configuration, usually resembling a noble gas (octet rule). This can happen in two main ways:
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Covalent Bonding: Atoms share valence electrons to achieve a stable configuration. This type of bonding typically occurs between nonmetal atoms. The shared electrons are attracted to the nuclei of both atoms involved in the bond, holding them together. Example: The bonding in a water molecule (H₂O).
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Ionic Bonding: Atoms transfer valence electrons from one atom to another. This usually occurs between a metal and a nonmetal. The atom that loses electrons becomes a positively charged ion (cation), and the atom that gains electrons becomes a negatively charged ion (anion). The electrostatic attraction between these oppositely charged ions forms the ionic bond. Example: The bonding in sodium chloride (NaCl, table salt).
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Metallic Bonding: In metals, valence electrons are delocalized and form a "sea of electrons" surrounding positively charged metal ions. This sea of electrons is attracted to all the metal ions, holding the metal together. This explains why metals are good conductors of electricity because electrons are free to move throughout the structure.
In summary, chemical bonding arises from the interaction of valence electrons, leading to attraction between atoms via shared or transferred electrons, ultimately driven by the attraction between electrons and atomic nuclei.
