Question

Cl₂(g) ⇌ 2Cl(g)

What is happening to the entropy in the following reaction? If entropy changes, what is the sign of ΔS?

H₂O(g) ⇌ ½ O₂(g) + H₂₍g)

What is happening to the entropy in the following reaction? If entropy changes, what is the sign of ΔS?

Ag⁺(aq) + Cl^-(aq) ⇌ AgCl(s)

What is happening to the entropy in the following reaction? If entropy changes, what is the sign of ΔS?

Answer 1

Cl2(g) ⇌ 2Cl(g)

$\Delta$S   = S0f products - S0 f reactants

       = 2*165.198-223.066

        = 107.33J/K

$\Delta$S is positive.

The number of partilces are increases randomness is increases. The entropy change is increases. $\Delta$ S is +ve

H2O(g) ⇌ ½ O2(g) + H2(g)

$\Delta$S   = S0f products - S0 f reactants

          = 130.684+1/2*205-188.825

           = 130.684+102.5-188.825

         = 44.359J/K

$\Delta$S is positive.

The number of partilces are increases randomness is increases. The entropy change is increases. $\Delta$ S is +ve

Ag+(aq) + Cl-(aq) ⇌ AgCl(s)

$\Delta$S   = S0f products - S0 f reactants

       = 96.2-(72.676+56.484)

       = -32.96J/K

$\Delta$S is -ve

The aqueous solution convert to solid randomness is decreases. The entropy change is decreases. $\Delta$ S is -ve