Final answer:
To determine the equilibrium partial pressure of SO2 when using calcium oxide to remove it from smokestack gases, one typically utilizes the equilibrium constant Kp along with the initial conditions, but the question lacks sufficient details for calculation.
Step-by-step explanation:
The question inquires about the equilibrium partial pressure of sulfur dioxide (SO2), if calcium oxide (CaO) is used to remove SO2 from smokestack gases and the partial pressure of oxygen (O2) is 0.21 atm. The reaction is 2CaO (s) + 2SO2 (g) + O2 (g) → 2CaSO4(s), with a given equilibrium constant Kp of 2.38. However, the information provided does not include enough details to calculate the equilibrium partial pressure of SO2.
Typically, you would use the Kp value along with the initial conditions and stoichiometry of the reaction to find the equilibrium pressures, but this information is absent in the question. In practical applications, calcium oxide is an important material in removing pollutants like SO2 and in industrial processes, including acid rain prevention and steelmaking. It serves as a scrubber by reacting with sulfur dioxide to form compounds such as calcium sulfite.