Respuesta :
Answer:
197.8 J/(mol•K).
Explanation:
- ∆S° = [Σ bS° products] - [Σ aS° reactants], where b and a are the coefficients of the products and the reactants in the balanced reaction equation.
Br₂(l) ⟶ 2 Br(g)
∴ ∆S° = [2 x S° Br(g)] - [S° Br₂(l)]
∴ ∆S° = [(2)(175.0 J/(mol•K)] - [152.2 J/(mol•K)] = 197.8 J/(mol•K).
Answer:
197.8 J/mol
Explanation:
The conversion will happen in steps. First, the Br₂(l) will be converted to Br₂(g), and then to Br atoms. Thus, the change in entropy will be the sum of the change in entropy of the two steps.
Step 1
Br₂(l) → Br₂(g)
ΔS = ∑n*S°products - ∑n*S°reactants, where n is the stoichiometric coefficient
ΔS = 245.5 - 152.2 = 93.3 J/K
Step 2
Br₂(g) → 2Br(g)
ΔS = (2*175.0) - 245.5 = 104.5 J/mol
Thus, the total change in entropy is
ΔS = 93.3 + 104.5
ΔS = 197.8 J/mol