The value of Henry’s constant K_H is

The value of Henry's constant K_H​ is greater for gases with lower solubility because of the mathematical relation -

$$\begin{gathered} \mathrm{P}={\mathrm{K}}_{\mathrm{H}}\mathrm{X} \\ {\mathrm{K}}_{\mathrm{H}}=\frac{\mathrm{P}}{\mathrm{X}} \end{gathered}$$

where, K_H​ represents Henry's constant, p is partial pressure of the gas in vapour phase, and x denotes mole fraction of the gas in solution.

Thus KH​ is inversely proportional to mole fraction of gas in solution (representing its solubility).