What Is the Thickness of a One-Molecule-Thick Oil Layer on Water?

[BogMonkey]

Homework Statement

A spherical drop of oil, 1 mm in diameter, falls on a water surface. The oil spreads out to cover a circular patch of diameter 60 cm. The oil spreads out until it forms a uniform layer on top of the water, only one molecule thick. What is the thickness of this layer?

Homework Equations

The Attempt at a Solution

I have no idea how they want me to answer this. It states in the question that the layer is 1 molecule thick but I have no idea what type of oil it is so I don't know what thick a molecule of this oil is.

 

[mgb_phys]

That's what you are trying to find out!
it's a simple geometry question, the volume of oil doesn't change.