A drop of oil with a volume of 0.003 mm3 spread over the surface of the water in a thin layer.

A drop of oil with a volume of 0.003 mm3 spread over the surface of the water in a thin layer. Knowing that the average diameter of an oil molecule is 0.0000001 mm, determine the area of the oil layer on the water surface.

The volume of the oil layer can be represented as the product of the area of the oil layer by its thickness:

V = S * h, where V is the volume of a drop of oil (V = 0.003 mm3 = 0.003 * 10-9 m3), S is the required area of the oil (m2), h is the thickness of the oil layer (h = d (diameter of the oil molecule) = 0.0000001 mm = 0.0000001 * 10-3 m).

Calculation formula: S = V / d.

Let’s make a calculation: S = 0.003 * 10-9 / 0.0000001 * 10-3 = 0.03 m2 = 300 cm2.

Answer: The area of the oil layer on the water surface is 0.03 m2 or 300 cm2.