# Which of the following is INCORRECT?

(1) Adsorption is always exothermic

(2) FeCl$_3$ is preferred over KCl to treat a cut due to bleeding

(3) The enthalpy of adsorption of chemisorption is high

(4) When a solution of acetic acid in water is shaken with charcoal the concentration of the acid decreases in the solution

$\begin{array}{1 1} (1) \;and (3) \\ (2)\;and;(4) \\ All \;of\;the\;above \\ none\;of\;the\;above \end{array}$

(1) Adsorption is always exothermic $\rightarrow$ Adsorption causes a decrease in the residual forces on the surface of the adsorbent, leading to a decrease in the surface energy of the adsorbent, which makes it exothermic.
(2) FeCl$_3$ is preferred over KCl to treat a cut due to bleeding $\rightarrow$ FeCl$_3$ helps in coagulation of blood more effectively than KCl.
(3) The enthalpy of adsorption of chemisorption is high $\rightarrow$ In chemisorption, there is a transfer or sharing of electron, or breakage of the adsorbate into atoms or radicals which are bound separately. Because of this chemical bond formation, the enthalpy is high compared to Physical adsorption.
(4) When a solution of acetic acid in water is shaken with charcoal the concentration of the acid decreases in the solution $\rightarrow$ This is true and because part of the acid is adsorbed by charcoal
Since, all 4 statements are true, the correct answer is (D), None of the above.
answered Mar 17, 2014