The Difference Between Intermolecular Forces and Intramolecular Forces
By: Dania Kaikati
Different Types of Forces of Attraction
Intramolecular Forces:
- Ionic bond - when one atom takes an electron away from another and the resulting positive and negative ions are attracted to each other
- Covalent bonds - (both polar and non-polar) this bond is formed between atoms that have similar electronegativitie. a polar covalent bond is formed when atoms of slightly different electronegativities share electrons . non-polar bond is when formed between same atoms or atoms with very similar electronegativities—the difference in electronegativity between bonded atoms is less than 0.5.
- Metallic bond - a type of chemical bond that occurs between atoms of metallic elements.
Intermolecular Forces
Dipole-dipole interactions: Dipole-dipole interactions are electrostatic interactions between the permanent dipoles of different molecules.
Hydrogen Bonding: special kind of dipole-dipole interaction that occurs specifically between a hydrogen atom bonded to either an oxygen, nitrogen, or fluorine atom.
London dispersion forces: forces caused by correlated movements of the electrons in interacting molecules, which are the weakest of intermolecular forces and are categorized as van der Waals forces.The more electrons a molecule has, the stronger the London dispersion forces are.
(Continued)
Ionic forces - ionic forces are interactions between charged atoms or molecules (“ions”). Positively charged ions, such as Na(+) , Li(+), and Ca(2+), are referred to as cations. Negatively charged ions, such as Cl(–), Br(–), HO(–) are called anions
Ion-dipole forces - An ion-dipole force is an attractive force that results from the electrostatic attraction between an ion and a neutral molecule that has a dipole.
The Stronger of the Two Forces
Which one is Stronger?
Intermolecular forces are much weaker than the intramolecular forces of attraction but are important because they determine the physical properties of molecules like their boiling point, melting point, density, and enthalpies of fusion and vaporization. All molecules, ions, and atoms have these forces but the strength of them is much less than that seen in bonds. But the strength of the IMFs varies greatly with the type of molecule (polar vs. non-polar) and the presence of certain groups, such as hydrogen
The difference between the strength of the two forces
Picture Citations
- Gases, Liquids, and Solids, www.chem.purdue.edu/gchelp/liquids/character.html.
- https://qph.fs.quoracdn.net/main-qimg-2af86e198ac8de4a9cf3d8b198ca8cbe
- https://biodifferences.com/wp-content/uploads/2018/07/ionicbond.jpg
- https://www.chem.purdue.edu/gchelp/liquids/ions.gif
- https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcRAKaJeUlob2d8Bmnyba31Ud6mY9n3AzEnNpTOFe2zpziBo1w16kA
- http://wps.prenhall.com/wps/media/objects/3311/3391416/imag1102/AAAUAYX0.JPG
- Dipole-Dipole Forces, www.chem.purdue.edu/gchelp/liquids/dipdip.html.
- https://chem.libretexts.org/@api/deki/files/8906/H_bond_diagram_1.jpg?revision=1&size=bestfit&width=354&height=176
Intramolecular Forces vs. Intermolecular Forces
Table
Citations
Sources
- Boundless. “Boundless Chemistry.” Lumen, courses.lumenlearning.com/boundless-chemistry/chapter/intermolecular-forces/.
- “Intramolecular and Intermolecular Forces.” Khan Academy, Khan Academy, www.khanacademy.org/test-prep/mcat/chemical-processes/covalent-bonds/a/intramolecular-and-intermolecular-forces.
- “Ion-Dipole Interactions.” Brilliant Math & Science Wiki, brilliant.org/wiki/ion-dipole-interactions/.
- “Covalent Bond.” Covalent Bond - an Overview ScienceDirect Topics, www.sciencedirect.com/topics/chemistry/covalent-bond.