# Henry's constant and solubility

According to Henry's law

The solubility of gas in a liquid is directly proportional to the partial pressure i.e S=Kp

My book says that higher the value of K at a given pressure lower is the solubility of the gas in the liquid. I don't understand how. I know I am overseeing something really simple over here as all the books that I have and online websites seem to conclude the same from the given equation. A little help maybe. Thanks.

Actually solubility $x$ is given as a function of pressure $p$ and henry's constant $K_H$: $$p=K_Hx$$

My book says that higher the value of K at a given pressure lower is the solubility of the gas in the liquid. I don't understand how.

Since at a given pressure, $p$ is constant, if you increase $K_H$, logically solubility $x$ would decrease.

• My book says that x is mole fraction! :( – Karan Singh Apr 21 '15 at 15:19
• @KaranSingh mole fraction can be treated as an indirect measure of solubility. – RE60K Apr 21 '15 at 15:20
• So would it be correct to say that mole fraction is directly proportional to solubility? – Karan Singh Apr 21 '15 at 15:21
• @KaranSingh approximately for dilute solutions. – RE60K Apr 21 '15 at 15:21