0
$\begingroup$

I was thinking about molecular attraction and a question suddenly struck in my mind which is 'Why do two molecule of an element attract each other?'

The answer is easy when we discuss about compound materials. The molecules of a compound have dipoles that can attract each other. But what happens about elements? The molecules of an element don't have dipoles.

After so many attempts, I thought there are only two particles in those molecules that can attract each other — Neucleus and Electron. But also there works repulsive forces between the electrons and between the neucleus of two molecules. It seems like the repulsion is stronger attraction.

So how the attraction force get stronger than the repulsion force so that two molecules of an element attract each other?

$\endgroup$
6
  • $\begingroup$ this qualitative answer of mine may help physics.stackexchange.com/questions/262280/… . There are various types of bonding. $\endgroup$
    – anna v
    Apr 27 at 8:59
  • $\begingroup$ I didn't find here something what I am looking for. $\endgroup$ Apr 27 at 9:05
  • $\begingroup$ Have you studied quantum mechanics and its probabilistic nature ? $\endgroup$
    – anna v
    Apr 27 at 10:41
  • $\begingroup$ I have not studied quantum probabilistic nature yet. $\endgroup$ Apr 27 at 11:34
  • $\begingroup$ When you say molecular attraction do you mean the attraction between two different molecules of $O_2$ or do you mean the attraction between two atoms within a single molecule of $O_2$? Just naming $O_2$ as an example $\endgroup$ Apr 27 at 11:39

2 Answers 2

3
$\begingroup$

There are only seven elements which naturally form stable molecules, namely hydrogen, oxygen, nitrogen, fluorine, chlorine, bromine and iodine. At room temperature only iodine is a solid. When they do liquify or solidify, they do so as a result of Van Der Waals forces, which are electromagnetic in nature, acting at short range between the individual molecules. See https://en.wikipedia.org/wiki/Van_der_Waals_force

$\endgroup$
1
  • 2
    $\begingroup$ As a chemist, I can assure you there are several more, since you did not restrict to diatomic molecules. These include allotropes of sulfur, phosphorus, arsenic and the weird pairing in gallium. But your answer is good: +1. $\endgroup$
    – Ed V
    Apr 27 at 13:40
0
$\begingroup$

Van der Waals interaction causes mutual attraction of many if not all of the following elemental molecules H$_2$, Na$_2$, K$_2$, noble gas atomic molecules, S$_8$, O$_3$, O$_8$, F$_2$, Cl$_2$, buckyballs, carbon nanotubes, cyclocarbons. O$_2$ is magnetic, so here probably magnetic attraction dominates.

$\endgroup$
1
  • $\begingroup$ Van der Waals established his theory long before the magnetic dipole moment was predicted and observed on the atomic scale. Shouldn't this theory slowly be subjected to a critical examination? After all, atoms and molecules have a magnetic dipole moment rather than an electric polarisation. $\endgroup$ Apr 28 at 3:21

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.