0
$\begingroup$

This question already has an answer here:

According to the theory of London dispersion forces, intermolecular forces are created in non polar substances by induction of instantaneous dipole to neighbouring molecules. If that is the case then when we mix water and oil, water being polar should induce polarity in oil and they should mix. But they don't. Doesn't water induce polarity to oil? Do I have a false concept or something.

$\endgroup$

marked as duplicate by Ben Norris, ron, Klaus-Dieter Warzecha, Martin - マーチン, Curt F. May 16 '15 at 15:52

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

  • 2
    $\begingroup$ This question has already been answered: chemistry.stackexchange.com/questions/2734/…. The short version is: Water is so strongly attracted to itself that it excludes the oil. $\endgroup$ – Ben Norris May 16 '15 at 12:19
  • $\begingroup$ My question is that why polarity is not induced in oil $\endgroup$ – Saad May 16 '15 at 13:09
  • 1
    $\begingroup$ Water molecules do induce some polarity on the oil molecules when they meet, but the resulting interaction is still significantly weaker than mutual hydrogen bonding between water molecules, so the materials still separate phase almost completely. $\endgroup$ – Nicolau Saker Neto May 16 '15 at 14:15
0
$\begingroup$

Water is already very 'happy' with his own guys due to strong hydrogen bonds . While van der waals force is so weak that its presence is so little for it to be seen while there is hydrogen bond. So even though there is some dipole induced it isn't enough.

the total energy is lower than when they are mixed. The system is more stable if unmixed. -Chin Yeh

$\endgroup$

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