Steroids are a class of biologically active compounds that alter cell membrane fluidity and act as signaling molecules leading to gene expression. They are quite insoluble in water, but the osmotic pressure of dilute solutions can be used to determine their molar mass.

$1\mathrm{.}997$ mg of an unknown steroid $($one of those in the figure below$)$ was dissolved in $0\mathrm{.}175$ L of water at $309\mathrm{.}1$ K$.$ The osmotic pressure was determined to be $0\mathrm{.}9325$ mbar.