For the solution of the gases w ,   x ,   y and z in water at 298   K , the Henry's law…

${\mathrm{P}}_{\mathrm{g}\mathrm{a}\mathrm{s}}={\mathrm{K}}_{\mathrm{H}}.{\mathrm{X}}_{\mathrm{g}\mathrm{a}\mathrm{s}}$

Where, ${\mathrm{P}}_{\mathrm{g}\mathrm{a}\mathrm{s}}$ is the partial pressure of gas.

${\mathrm{K}}_{\mathrm{H}}$ is the Henry’s constant

${\mathrm{X}}_{\mathrm{g}\mathrm{a}\mathrm{s}}$ is the mole fraction of gas

${\mathrm{P}}_{\mathrm{g}\mathrm{a}\mathrm{s}}={\mathrm{K}}_{\mathrm{H}}\left(1-{\mathrm{X}}_{{\mathrm{H}}_2\mathrm{O}}\right)$

${\mathrm{P}}_{\mathrm{g}\mathrm{a}\mathrm{s}}={\mathrm{K}}_{\mathrm{H}}-{\mathrm{K}}_{\mathrm{H}}{\mathrm{X}}_{{\mathrm{H}}_2\mathrm{O}}$

On comparing this with the equation of straight line, $\mathrm{y}=\mathrm{mx}+\mathrm{c}$, the intercept, $\mathrm{c}={\mathrm{K}}_{\mathrm{H}}$. Thus, the gas having more value of Henry's law constant will have more value of intercept on the y-axis.