Which one of the following is not a property of physical adsorption?

If x gram of gas is adsorbed by m gram of adsorbent at pressure P, the plot of log $${x \over m}$$ versus log P is linear. The slope of the plot is :
(n and k are constants and n > 1)

Which of the following statements about colloids is False ?

Adsorption of a gas on a surface follows Freundlich adsorption isotherm. Plot of log $${x \over m}$$ versus log p gives a straight line with slope equal to 0.5, then:

( $${x \over m}$$ is the mass of the gas adsorbed per gram of adsorbent)