JEE Advanced · Chemistry · 19. Surface Chemistry
Methylene blue, from its aqueous solution, is adsorbed on activated charcoal at 25o C. For this process, the correct statement is
- A The adsorption requires activation at 25oC.
- B The adsorption is accompanied by a decrease in enthalpy
- C The adsorption increases with increase of temperature.
- D The adsorption is irreversible.
Answer & Solution
Correct Answer
(B) The adsorption is accompanied by a decrease in enthalpy
Step-by-step Solution
Detailed explanation
It is the process of Physical adsorption as charcoal is already activated.
Since physical adsorption is spontaneous is -ve
as is -ve (passage of methylene blue from aqueous phase over the surface of adsorbent) i.e. is highly -ve since process is exothermic in nature. Physical adsorption is reversible in nature.
Since physical adsorption is spontaneous is -ve
as is -ve (passage of methylene blue from aqueous phase over the surface of adsorbent) i.e. is highly -ve since process is exothermic in nature. Physical adsorption is reversible in nature.
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