bond angle

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bond angle

chemistry

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June 22, 2026

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The bond angle refers to the geometric arrangement of atoms in a molecule, specifically the angle formed between two chemical bonds that share a common atom. This arrangement is crucial for understanding molecular shapes and is often predicted using the Valence-Shell Electron-Pair Repulsion (VSEPR) theory. VSEPR theory posits that electron pairs (both bonding and lone pairs) around a central atom repel each other and arrange themselves to minimize these repulsions, thus dictating the molecule's shape and bond angles. For example, in methane (CH₄), the four electron pairs around the central carbon atom arrange tetrahedrally, resulting in bond angles of approximately 109.5°. In contrast, water (H₂O) has an angular shape due to two bonding pairs and two lone pairs, leading to a smaller bond angle of about 104°.123

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carbene
Electronic configuration and molecular structure.
The bond angle for the singlet state, however, is predicted to be larger than that for the triplet state. These predictions are fully supported by experiments. The simplest carbene, methylene, has been shown by a technique called electron magnetic resonance spectroscopy to have a triplet ground…
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The bond angle for the singlet state, however, is predicted to be larger than that for the triplet state. These predictions are fully supported by experiments. The simplest carbene, methylene, has been shown by a technique called electron magnetic resonance spectroscopy to have a triplet ground…
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hydrocarbon
Cycloalkanes
…smaller than the normal tetrahedral bond angle of 109.5° and imposes considerable strain (called angle strain) on cyclopropane. Cyclopropane is further destabilized by the torsional strain that results from having three eclipsed C―H bonds above the plane of the ring and three below.
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…smaller than the normal tetrahedral bond angle of 109.5° and imposes considerable strain (called angle strain) on cyclopropane. Cyclopropane is further destabilized by the torsional strain that results from having three eclipsed C―H bonds above the plane of the ring and three below.
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chemical bonding
Applying VSEPR theory to simple molecules
The angle between electron pairs in a tetrahedral arrangement is 109.5°. However, although H₂O is indeed angular and NH₃ is trigonal pyramidal, the angles between the bonds are 104° and 107°, respectively. In a sense, such close agreement is quite satisfactory for so simple an approach,…
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The angle between electron pairs in a tetrahedral arrangement is 109.5°. However, although H₂O is indeed angular and NH₃ is trigonal pyramidal, the angles between the bonds are 104° and 107°, respectively. In a sense, such close agreement is quite satisfactory for so simple an approach,…
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chemical bonding
The quantum mechanics of bonding
…varies as bond lengths and bond angles are changed. A typical curve for a diatomic molecule, in which only the internuclear distance is variable, is shown in Figure 10. The energy minimum of this curve corresponds to the observed bond length of the molecule. The depth of the minimum is…
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…varies as bond lengths and bond angles are changed. A typical curve for a diatomic molecule, in which only the internuclear distance is variable, is shown in Figure 10. The energy minimum of this curve corresponds to the observed bond length of the molecule. The depth of the minimum is…
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alcohol
Structure and classification of alcohols
… atoms, however, so the R―O―H bond angle in alcohols is generally larger than the 104.5° H―O―H bond angle in water. For example, the 108.9° bond angle in methanol shows the effect of the methyl group, which is larger than the hydrogen atom of water.
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… atoms, however, so the R―O―H bond angle in alcohols is generally larger than the 104.5° H―O―H bond angle in water. For example, the 108.9° bond angle in methanol shows the effect of the methyl group, which is larger than the hydrogen atom of water.
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