You can obtain a rough estimate of the size of a molecule by the following simple experiment. Let a droplet of oil spread out on a smooth water surface. The resulting oil slick will be approximately one molecule thick. Given an oil droplet of mass 10.00 multiplied by 10-7 kg and density 1174 kg/m3 that spreads out into a circle of radius 41.8 cm on the water surface, what is the diameter of an oil molecule?

1 answer

Density=mass/volume

Volume=mass/density

(10.00*10^-7 kg)/(1174 kg/m^3)= 8.518*10^-10 m^3

Volume=(height)(cross-sectional area)

Volume=h*pi*(.418 m)^2
Volume=h(.549 m^2)
h(.549 m^2)=8.518*10^-10 m^3
h=(8.518*10^-10 m^3)/(.549 m^2)
h~1.55*10^-9