Question

What is the density of hexane? Will hexane float on water?

Answer 1

Have you never seen an oil slick?

`rho_"hexanes"=0.66*g*mL^-1; rho_"water"=1.00*g*mL^-1`

Explanation:

Hexanes is certainly immiscible in water. Given the density, hexanes will float on water.

We take this from Archimedes of Syracuse, who in the 3rd century BC, stated " Any object, wholly or partially immersed in a fluid, is buoyed up by a force equal to the weight of the fluid displaced by the object.

When you use a separating funnel in chemistry, the hexanes layer will always be the top layer, and the aqueous layer is drained off first.