You probably know water and oil don't mix. Oil is hydrophobic and less dense than water so it will sit on top water. What you might not know is that the oil will spread out into the thinest possible sheet which can be considered 1 molecule thick. Benjamin Franklin showed that 2.39mL of oil would cover 1,806m2 of still water. What is the thickness of the layer of oil (in nm)? [This is also the length of a single molecule] The best shape to consider the oil is a cylinder. Recall that the volume of a cylinder is the height, h, multiplied by the area of the circle (pi* r2 ). V=hr2