Sulfur can be separated from lead in the mineral galena, PbS(s), by "roasting" the ore in the presence of oxygen as shown in the following reaction: 2PbS(s)+ 3O₂(g) $\rarr$ 2PbO(s)+ 2SO₂(g) Calculate $\Delta$S° for this reaction using the thermodynamic data provided below.

Question

Quizplus · Accepted Answer

The reaction involves the conversion of solid galena and oxygen gas to solid lead oxide and sulfur dioxide gas. To calculate the standard entropy change for the reaction, we can use the standard entropies of formation for each of the compounds involved:

ΔS° = ΣnS°(products) - ΣnS°(reactants)

ΔS° = [2S°(PbO(s)) + 2S°(SO2(g))] - [2S°(PbS(s)) + 3S°(O2(g))]

ΔS° = [(2)(64.8 J/K·mol) + (2)(248.1 J/K·mol)] - [(2)(91.6 J/K·mol) + (3)(205.0 J/K·mol)]

ΔS° = -161.5 J/K·mol

Therefore, the answer is B) -161.5 J/K·mol.

Sulfur Can Be Separated from Lead in the Mineral Galena →\rarr→

Sulfur Can Be Separated from Lead in the Mineral Galena $\rarr$