$1\mathrm{.}5$ The Henry constant $H^{\text{'}}=\frac{p}{x}$ for $N{H}_3$ in water at $20C$ is $2\mathrm{.}70$atm. Calculate the value of $H=\frac{p}{C},$ where $C$ is $kmol{m}^{-3},$ and $m=\frac{y}{x}$ where $x$ and $y$ are the mole fractions in the liquid and gas phases, respectively.