How big does an atom need to be to have dispersion forces be greater than other intermolecular forces? [closed]








**Closed**. This question needs [details or clarity](/help/closed-questions). It is not currently accepting answers.
 
 






---








**Want to improve this question?** Add details and clarify the problem by [editing this post](/posts/128434/edit).




Closed 3 years ago.








[Improve this question](/posts/128434/edit) 



I know as an atom gets bigger the dispersion forces grow with it. But how big does an atom, e.g methanoic acid, to have dispersion forces that outrank dipole-dipole forces?




I think you mean molecules, not atoms. Regardless let's just say you meant molecule and by intermolecular you're really just focusing on Dipole, the answer is- youre comparing apples to oranges. But you don't look at 1 molecule interacting with another rather a whole bunch of molecules interacting simultaneously. At some moment when electrons are gravitating toward 1 atom in a molecule and another molecule nearby has dipolarization and the relative distance can cause bonds to break and realign on another molecule. But I think what you mean is, what kind of atoms in a molecule would be impacted by dispersion force the most? And that's large molecules and also large atoms because large atoms like iodine, can have an induced dipole from a atoms its not bonded to much easier than a tiny atom. How big? There really isn't any way to answer that question. 


 0