A tube is coated on the inside with naphthalene and has an inside diameter of $20mm$ and a length

of $1\mathrm{.}10m.$ Air at $318K$ and of $101\mathrm{.}3$kPa flows through this pipe at a velocity of $0\mathrm{.}8\frac{m}{s}.$

Assuming that the pressure remains constant. Calculate the concentration of naphthalene in the

exist air