Entropy will decrease in A,B,C and D processes. A, B→ Freezing of water will decrease entropy as particles will move closer and forces of attraction will increase. This leads to a decrease in randomness. So, entropy decreases. (A) Water
0∘C
⟶
ice; ∆S=− ve (B) Water
−10∘C
⟶
ice; ∆S=− ve (C) N2(g)+3H2(g)⟶2NH3(g);∆S=− ve Number of moles are decreasing n=2−(3+1) n=−2 So, entropy decreases. (D) Adsorption; ∆S=− ve Adsorption will lead to a decrease in the randomness of gaseous particles. So, entropy decreases. (E) NaCl(s)⟶Na+(aq)+Cl−(aq);∆S>0 The number of species on product side is more than the number of species on reactant side. So, entropy increases on dissolution of NaCl in water.