Question

Calculate the change in entropy if Br2(l) is converted to Br2(g).

S° for Br2(l) = 152.2 J/(mol•K)
S° for Br2(g) = 245.5 J/(mol•K)
S° for Br(g) = 175.0 J/(mol•K)

Answer 1

Ans: The entropy change for the given reaction is 93.3 J/K

Given reaction:

Br2(l) → Br2(g)

ΔS = ∑n(products)S⁰(products) - ∑n(reactants)S⁰(reactants)

= 1 mole* S°(Br2(g)) - 1 mole*S°(Br2(l))

= 1 mole *245.5 J/mol-K - 1 mole*152.2 J/mol-K

= 93.3 J/K