a$)$ The liquid$-$liquid interfacial tension of $n-$hexane $($o$)$ and water $($w$)$ is $51\mathrm{.}1mN{m}^{-1}.$ Estimate based on the Fowkes equation the dispersion and specific surface tensions of water. The surface tensions of hexane and water are $18\mathrm{.}4$ and $72\mathrm{.}8mN{m}^{-1},$ respectively, at room temperature. Then, estimate the interfacial tension of perfluorohexane $(11\mathrm{.}5mNm{m}^{\text{'}})$ with water. Finally, estimate the interfacial tension between mereury $(485mN{m}^{-1})$ and water and compare the result with the experimental value $(426mNm{m}^{-1}).$ The experimental interfacial tension between mercury and octane $(21\mathrm{.}8mNm{N}^{-1})$ is $375mN{m}^{-1}.$ For $n-$hexane, which is a hydrocarbon, the dispersion part of the surfice tension is equal to the total surface tension $(18\mathrm{.}4mN{m}^{-1}).$