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Let's suppose you sample mercury in a polystyrene plastic test tube at 25 °C. Would it be expected that the meniscus of Hg is convex (upward curvature) ?

I assume that the only possible adhesion forces between Hg and polystyrene are London dispersion forces and that they are weaker than the cohesion forces between Hg atoms (metallic bonding more stable even considering that Hg is liquid at room temperature).

Am I right ?

Thanks!

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    $\begingroup$ You're pretty much right. What more would you wanna know then? $\endgroup$
    – Mithoron
    Commented Jun 5 at 20:25
  • $\begingroup$ If the weak metallic bonds in Hg can be exceeded by the global London dispersion forces between polystyrene and Hg. If so, it will affect the curvature of the meniscus. $\endgroup$
    – Tom
    Commented Jun 5 at 20:45
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    $\begingroup$ Believe it or not, metallic bonding in Hg arises from dispersion forces. Its single atoms are so good at it there's pretty much no way "normal" stuff is gonna beat it at its game. Hg does dissolve most of metals, though so it's gonna wet them too. $\endgroup$
    – Mithoron
    Commented Jun 5 at 21:20
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    $\begingroup$ As @Mithoron implies, in a silver, copper or gold tube, the mercury would inch... oops, centimeter its way up the wall, forming a concave meniscus viewed from above. (After some time, it would dissolve right into the tube wall.) In an iron tube, the meniscus would be convex, as the Hg coheres to itself more strongly than it adheres to iron. $\endgroup$
    – DrMoishe Pippik
    Commented Jun 6 at 3:47
  • $\begingroup$ A brief google search reveals this picture for liquid mercury in a 1/2" diameter tube with 1/8" walls of lexan (as reported here), a trademark for a polycarbonate. So the answer is yes equally for this polymer. $\endgroup$
    – Buttonwood
    Commented Jun 6 at 14:55

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