Question

Which of the following represents correctly the variation of surface tension T with temperature $\theta$?

• A. $T\propto {\theta }_c-\theta$
• B. $T\propto {\theta }_c-{\theta }^{-1}$
• C. $T\propto {\theta }_c-{\theta }^0$
• D. $T\propto {\theta }_c-{\theta }^{-2}$

Answer 1

The correct option is A $T\propto {\theta }_c-\theta$

According to the Eotvos Rule, that gives a relationship between the surface tension of a liquid and its temperature,

T = k $V^{-2/3}({\theta }_c-\theta )$

where, T is the surface tension

k is a constant valid for all liquids

V is the molar volume of the liquid

${\theta }_c$ is the critical temperature of the liquid

$\theta$ is the actual temperature