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Methylene blue, from its aqueous solutio...

Methylene blue, from its aqueous solution, is adsorbed on activated charcoal at `25^(@)C` . Identify correct one
(a)The adsorption requires activation at `25^(@)C`
(b)The adsorption is accompanied by a decrease in enthalpy
(c)The adsorption increases with increases of temperature
(d)The adsorption is irreversible

A

The adsorption requires activation at `25^@C`

B

The adsorption is accompanied by a decrease in enthalpy

C

The adsorption increases with increase of temperature

D

The adsorption is irreversible

Text Solution

Verified by Experts

Physical adsorption takes place with decrease in enthalpy thus exothermic change. It is physical adsorption and does not require activation. Thus, (a) is incorrect
Being physical adsorption thus, (b) is correct. Exothermic reaction is favoured at low temperature thus (c) is incorrect. Physical adsorption is always reversible, thus (d) is incorrect.
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