Question

The salting-out process occurs spontaneously. Can you explain the reason for this spontaneity with free energy, enthalpy and entropy concepts

Answer 1

• Salting out or generally known as Protein precipitation is a spontaneous reaction as said. It is the process of addition of a neutral salt which compresses the solvation layer and increases the interaction between protein molecules.
• A spontaneous reaction has a negative Gibb's free energy value.
• We know that G = H - TS.

G = decreases (neagative) : shows that the reaction is spontaneous.

H = decreases (neagative) : supports the spontaneity.

S = decreases largely (negative) : the particles from solvation layer are brought into the bulk so as to move more freely, hence, lesser entropy.