AP EAMCET201825 Apr 2018Morning ShiftChemistrySurface ChemistryActual
Freundlich adsorption isotherms for the physical adsorption of a gas at temperature T 1 , T 2 and T 3 are shown in the graph given below. The correct relationship between T 1 , T 2 and T 3 is
Options
- AT 1 < T 2 < T 3
- BT 3 < T 1 < T 2
- C  T 3 < T 2 < T 1
- DT 2 < T 1 < T 3
Correct answer
C.   T 3 < T 2 < T 1
Step-by-step solution
Freundlich adsorption isotherm: This gives an empirical relationship between the quantity of a gas adsorbed by a unit mass of solid adsorbent and pressure at a particular temperature. It is expressed as: x m = k · p 1 / n   n > 1 ⇒ log x m = log   k + 1 n log   P Since adsorption is an exothermic process, it decreases with increase in temperature and varies inversely proportional to temperature. x m ∝ 1 T So, according to the given graph, x m is more for T 3 . So, T 3 is the leas