Question $1$: Hydrogen gas at $2\mathrm{.}5$atm pressure and $298K$ flows through a spherical shell made of vulcanized rubber with ID $50mm$ and OD $60mm.$ The solubility of $H_2$ is $5\mathrm{.}3{10}^{-2}c{m}^3($STP$)c{m}^{-3}$atm and diffusivity of $H_2$ through rubber is $1\mathrm{.}8{10}^{-6}c{m}^2{s}^{-1}.$ Estimate the rate of loss of $H_2$ by diffusion per meter of shell length.

$5$