electron pair
Quick Summary
An electron pair refers to two electrons that are either associated with a single atom or shared between two atoms, forming a chemical bond. In chemistry, these pairs are crucial for understanding how atoms connect to form molecules.1
Covalent Bonds and Electron Pairs
Covalent bonds, typically formed between nonmetal elements, involve the sharing of electron pairs between atoms. This sharing allows each atom to achieve a more stable electron configuration, often resembling that of a noble gas. For instance, in hydrogen chloride (HCl), a single shared electron pair forms the covalent bond between hydrogen and chlorine. These shared pairs are called bonding pairs, while unshared pairs on an atom are known as lone pairs.23
The Valence Shell Electron-Pair Repulsion (VSEPR) theory utilizes the concept of electron pairs to predict molecular shapes. It posits that electron pairs (both bonding and lone pairs) around a central atom repel each other, and the molecule adopts a shape that minimizes these repulsions.4
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- Gilbert N. Lewis
to chemical thermodynamics, the electron-pair model of the covalent bond, the electronic theory of acids and bases, the separation and study of deuterium and its compounds, and his work on phosphorescence and the triplet state (in which the quantum number for total spin angular momentum
Read Moreto chemical thermodynamics, the electron-pair model of the covalent bond, the electronic theory of acids and bases, the separation and study of deuterium and its compounds, and his work on phosphorescence and the triplet state (in which the quantum number for total spin angular momentum
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chemical bondingLewis formulation of a covalent bond…covalent bond is a shared electron pair. The bond between a hydrogen atom and a chlorine atom in hydrogen chloride is formulated as follows:
Read More…covalent bond is a shared electron pair. The bond between a hydrogen atom and a chlorine atom in hydrogen chloride is formulated as follows:
Read More- chemical bondingElectron-deficient compounds
…no justification for regarding an electron pair as the central feature of a covalent bond. Indeed, there are species that possess bonds that rely on the presence of a single electron. (The one-electron transient species H2+ is an example.) Nevertheless, in spite of these difficulties, Lewis’s approach to bonding has…
Read More…no justification for regarding an electron pair as the central feature of a covalent bond. Indeed, there are species that possess bonds that rely on the presence of a single electron. (The one-electron transient species H2+ is an example.) Nevertheless, in spite of these difficulties, Lewis’s approach to bonding has…
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- spectroscopyElectronic transitions
…can be occupied by a pair of electrons having opposite electron spins. The energy of each electron in a molecule will be influenced by the motion of all the other electrons. So that a reasonable treatment of electron energies may be developed, each electron is considered to move in an…
Read More…can be occupied by a pair of electrons having opposite electron spins. The energy of each electron in a molecule will be influenced by the motion of all the other electrons. So that a reasonable treatment of electron energies may be developed, each electron is considered to move in an…
Read More - chemical bondingMolecular orbitals of H2 and He2
The central importance of the electron pair for bonding arises naturally in MO theory via the Pauli exclusion principle. A single electron pair is the maximum number that can occupy a bonding orbital and hence give the greatest lowering of energy. However, MO theory goes beyond Lewis’s approach by not…
Read MoreThe central importance of the electron pair for bonding arises naturally in MO theory via the Pauli exclusion principle. A single electron pair is the maximum number that can occupy a bonding orbital and hence give the greatest lowering of energy. However, MO theory goes beyond Lewis’s approach by not…
Read More