Adsorption, if spontaneous, is exothermic. Explain.
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Adsorption is accompanied by decrease in entropy, i.e., `DeltaS=-ve` . If it is spontaneous than `DeltaG` should be negative `DeltaG=DeltaH-TDeltaS` . Since `DeltaS` is -ve (entropy decreases in the process of adsorption), `deltaG` will be negative, only if `DeltaH=-ve` , i.e., if the process is exothermic.
Assertion : For adsorption DeltaG, DeltaH, DeltaS all have –ve values Reason : Adsorption is a spontaneous exothermic process in which randomness decreases due to force of attraction between adsorbent and adsorbate.
Why adsorption is exothermic ?
Assertion :- The graphical representation of physical adsorption with temp is Reason :- This is weak adsorption & adsorption is exothermic process.
Adsorption of a gas on the surface of solid is sgenerally accompanied by decrease in entropy but still it is spontaneous in naturre. Explain.
(A) For adsorption DeltaG , DeltaS , and DeltaH all have negative value. (R) Adsorption is a spontanous process accompained by decrease in randomness.
Theory of spontaneous generation explains
Spontaneous adsorption of a gas on a solid surface is exothermic process because
Fill in the blanks by putting appropriate choices. During adsorption there is _______ in enthalpy and _______ in the entropy of a system by adsorption is a spontaneous process and thus DeltaG must be ________. Rate of physisorption ________ with increase in pressure.
