Just like those whose focus is primarily on water quality, researchers and practitioners who focus on air quality are often interested in gas$/$liquid exchange reactions. In the air quality literature, it is common to write the expression for flux in terms of a driving force based on gas$-$phase composition. That is$,$ the flux of a volatile species into the gas phase is written as $J_G=K_{G}a(c_G^{**}-c_G),$ where $c_G^{**}$ is the gas$-$phase concentration that would be in equilibrium with the bulk liquid, and a might be either $a_L$ or $a_R.$

A solution at $25C$ that contains $4\mathrm{.}5m\frac{g}{L}$ DO is in contact with the normal atmosphere, and is being aerated by a system with $K_{L}a=0\mathrm{.}2mi{n}^{-1}.$ Compute $c_G,c_G^{**},c_L^{**},J_L,J_G$ and $K_{G}a$ in the system.