Why are intermolecular forces weaker than covalent or ionic bonds (intramolecular forces)?
Intermolecular forces are weaker than intramolecular forces. Intramolecular forces in this case include bonding forces within a molecule from ionic and covalent bonds. Intermolecular forces are forces between different molecules and include things like London dispersion forces, Van der Waals forces, and dipole-dipole interactions. Intramolecular forces are stronger because they involve the actual sharing of electrons for covalent bonds. This sharing of electrons gives each element of the bond an octet of electrons in the valence shell which is a highly stable electronic configuration. Ionic bonds involve strong electrostatic interactions between ions. By comparison, intermolecular interactions do not involve the sharing or transfer or electrons and electrostatic interactions like hydrogen bonding only involve partial charges, not fully charged ions.
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