QUestion $5$

Imagine a pharmaceutical company that produces transdermal patches containing acetic acid as an active ingredient. These patches are designed to slowly release acetic acid into the skin for therapeutic purposes. To ensure consistent drug delivery, a thin film of non$-$diffusing water solution acts as a barrier in the patch structure. In this case, the film thickness is $1\mathrm{.}75mm,$ and the temperature is maintained at $293K$ to mimic typical storage conditions. On one side of the film, the concentration of acetic acid, expressed as weight percentage, is $18\%.$ On the other side, the concentration is $7\%$ acid. By calculating the rate of diffusion of acetic acid through the film, the pharmaceutical company can assess the patch's performance and determine if the desired release rate is achieved. Calculate the rate of diffusion of acetic acid across the film of non$-$diffusing water.