Final answer:
The calculation of the partial pressure of SO₂ at equilibrium with air and CaO requires a reversible reaction and corresponding equilibrium constant. The information given, however, provides a non-reversible reaction, making it impossible to determine the partial pressure of SO₂ without additional data or a correct reversible reaction.
Step-by-step explanation:
To calculate the partial pressure of SO₂ (sulfur dioxide) in equilibrium with air and solid CaO (calcium oxide), we can use the equilibrium constant (K﹡) provided for the reaction:
2CaO (s) + 2SO₂ (g) + O₂ (g) → 2CaSO4 (s)
However, the information provided in the question is not sufficient to solve this problem because the equation provided does not reflect a correct chemical reaction that reaches equilibrium (as it is a complete reaction converting reactants to products without a reversible process). Normally, one would use the equation for K﹡ and set up an expression using the partial pressures of the gases involved. The partial pressures of SO₂ and O₂ would be raised to their stoichiometric coefficients in the reaction. If the reaction were reversible, you'd find:
K﹡ = (P_CaSO4)0/(P_SO₂2 · P_O₂)
Since solid calcium sulfate doesn't have a partial pressure, its exponent is zero and can be omitted from the expression. Providing K﹡ and P_O₂ (which is 0.21 atm for O₂ in air), you could solve for P_SO₂:
2.38 × 1015 = 1/(P_SO₂2 · 0.21)
But without a correct reversible reaction, we cannot proceed to solve for P_SO₂. If we had a correct reversible reaction, and relevant data, you could rearrange this equation to solve for the partial pressure of SO₂. Without further information, or a reversible reaction, the calculation cannot be completed accurately.