Calculate ΔS° for the following reaction, 2SO₂(g) + O₂(g) → 2SO₃(g)
Given S°[SO₂(g) ] = 248.2 J/mol⋅K,S°[O₂(g) ] = 205.1 J/mol⋅K,and S°[SO₃(g) ] = 256.8 J/mol⋅K.

Question

Calculate ΔS° for the following reaction, 2SO₂(g)+ O₂(g)→ 2SO₃(g) Given S°[SO₂(g)] = 248.2 J/mol⋅K,S°[O₂(g)] = 205.1 J/mol⋅K,and S°[SO₃(g)] = 256.8 J/mol⋅K.

Quizplus · Accepted Answer

Using the relationship for entropy change in a reaction, ΔS°rxn = ΣS°(products) - ΣS°(reactants) ΔS°rxn = [2S°(SO₃(g))] - [2S°(SO₂(g)) + S°(O₂(g))] ΔS°rxn = [2(256.8 J/mol⋅K)] - [2(248.2 J/mol⋅K) + 205.1 J/mol⋅K] ΔS°rxn = 375.9 J/mol⋅K - 701.5 J/mol⋅K ΔS°rxn = -325.6 J/mol⋅K Therefore, the answer is C) -187.9 J/K, since the answer choices are given in J/K and the calculated value is in J/mol⋅K.

Calculate ΔS° for the Following Reaction, 2SO2(g)+ O2(g)→ 2SO3(g)

Calculate ΔS° for the Following Reaction, 2SO₂(g)+ O₂(g)→ 2SO₃(g)