How does a liquid's vapour pressure affect its surface tension?

i.e. to say, if a liquid's vapour pressure increases, will the surface tension increase or decrease?

The SERP for this question yields only research papers to which I don't have access. This theory isn't given in my textbook either.

  • 1
    $\begingroup$ Your cause and effect is backward. A decreasing surface tension increases vapor pressure. though you ussually can't control surface tension as an independent variable. $\endgroup$ – A.K. Dec 9 '17 at 17:04
  • $\begingroup$ @A.K. Oh! Actually, in my test paper, the statement was "A liquid with low vapour pressure will have high surface tension ", that's why I had framed the question this way. But, what is the reason for "decreasing surface tension increases vapor pressure"? $\endgroup$ – Gaurang Tandon Dec 9 '17 at 17:08

High surface tension is caused by strong intermolecular forces, the same are responsible for a low vapour pressure.

It is however quite a different matter to put a molecule on a surface and to completely strip it from a condensed phase and put it into the gas phase. There sure is no (inverse) proportionality or similar between vapour pressure and surface tension, and they don't "affect" each other.

A really stupid test question, imo.


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.