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There are many types of intermolecular forces (IMFs).
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The first of these is the set of Vander Waals forces, which do not involve ions.
Within this set, there are three main types of forces:

βœ¨βœ¨βœ¨πΏπ‘œπ“ƒπ’Ήπ‘œπ“ƒ π’Ήπ’Ύπ“ˆπ“…π‘’π“‡π“ˆπ’Ύπ‘œπ“ƒ π’»π‘œπ“‡π’Έπ‘’π“ˆ

β–ͺ️These forces do not involve polar molecules.
β–ͺ️AKA Induced dipole - induced dipole forces
β–ͺ️All molecules experience LDFs (since all have an induced dipole)
β–ͺ️Examples: Brβ‚‚, Iβ‚‚

Note that in the image above, these are induced dipoles - basically electrons being in random places creates incredibly weak dipoles (This is why LDFs are so weak!)

βœ¨βœ¨βœ¨π’Ÿπ’Ύπ“…π‘œπ“π‘’-π’Ήπ’Ύπ“…π‘œπ“π‘’ π’»π‘œπ“‡π’Έπ‘’π“ˆ

β–ͺ️These forces do involve polar molecules.
β–ͺ️Examples: CH₃Cl, PCl₃

βœ¨βœ¨βœ¨π»π“Žπ’Ήπ“‡π‘œπ‘”π‘’π“ƒ π’·π‘œπ“ƒπ’Ήπ’Ύπ“ƒπ‘”

β–ͺ️These forces involve hydrogen and nitrogen, oxygen, or fluorine. You can remember this through the mnemonic device NOF.
β–ͺ️Examples: Hβ‚‚0, NH₃, HF
β–ͺ️Fun fact: Hydrogen bonding is why water has so many unique properties!

Source: 2019 AP Exam Scoring Guides

πŸŒŸπŸŒŸπŸŒŸπΌπ‘œπ“ƒ-π’Ήπ’Ύπ“…π‘œπ“π‘’ π’»π‘œπ“‡π’Έπ‘’π“ˆ

β–ͺ️These forces involve both polar molecules and ions, and are typically salts in water.
β–ͺ️Examples: NaCl in Hβ‚‚0, NBr in Hβ‚‚0Β 


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It is important to note that ionic bonding is absent from this list of IMFs. Technically speaking, ionic bonds are not intermolecular forces due to the lack of covalent bonds.
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β–ͺ️As strength of the bond/force increases, so do melting and boiling point.
β–ͺ️In order from weakest to strongest forces:
London dispersion forces, Dipole-dipole forces, Hydrogen bonding, Ion-dipole forces, Ionic bonding.

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