Which one of the following chargcterisitic is associated with adsorption?

Options

A. `DeltaG, DeltaH` and `DeltaS` all are negative
B. `DeltaG` and `DeltaH` are negative but `DeltaS` is positive
C. `DeltaG` and `DeltaS` are negative but `DeltaH` is positive
D. aqueous solution of slaked lime

Answer

A

Explanation

Adsorption is a spontaneous process that occurs with release in energy and decrease in the randomness (i.e. entropy) of the adsorbed substance. For a spontaneous process. `DeltaG` must be negative
`DeltaG = DeltaH - TDeltaS`
As the process is exothermic and randomness of molecule (entropy) decreases hence, both `DeltaH` and `DeltaS` will be negative as well.