lone pair
Quick Summary
In chemistry, a lone pair refers to a pair of valence electrons that are not shared with another atom in a covalent bond and are not involved in the formation of a chemical bond. These electron pairs are located in the outermost electron shell of an atom and are crucial for understanding molecular shapes and chemical reactivity.123
The Valence-Shell Electron-Pair Repulsion (VSEPR) theory utilizes the concept of lone pairs. This theory posits that electron pairs, both bonding and non-bonding (lone pairs), repel each other. The arrangement of atoms in a molecule is determined by the need to minimize these repulsions, thus dictating the molecule's shape. For instance, the angular shape of a water molecule (H₂O) is a result of the two lone pairs on the oxygen atom pushing the two bonding pairs closer together.24
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chemical bondingThe hydrogen bond… orbital and to consider a lone pair of electrons on B as occupying a B orbital. When the three atoms are aligned, these three orbitals can form three molecular orbitals: one bonding, one largely nonbonding, and one antibonding. There are four electrons to accommodate (two from the original A―H bond…
Read More… orbital and to consider a lone pair of electrons on B as occupying a B orbital. When the three atoms are aligned, these three orbitals can form three molecular orbitals: one bonding, one largely nonbonding, and one antibonding. There are four electrons to accommodate (two from the original A―H bond…
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iceThe water moleculeKnown as the lone-pair orbitals, these are the keys to water’s peculiar behaviour, in that they attract the hydrogen nuclei of adjacent water molecules to form what are called hydrogen bonds. These bonds are not especially strong, but, because they orient the water molecules into a specific configuration,…
Read MoreKnown as the lone-pair orbitals, these are the keys to water’s peculiar behaviour, in that they attract the hydrogen nuclei of adjacent water molecules to form what are called hydrogen bonds. These bonds are not especially strong, but, because they orient the water molecules into a specific configuration,…
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