To determine the partial pressure of O2 in a mixture held in a 15.20 L vessel at 15 degrees Celsius, we would need additional information about the composition of the mixture. The partial pressure of a specific gas depends on its mole fraction in the mixture and the total pressure of the system.
If we have the mole fraction of O2 in the mixture and the total pressure, we can calculate the partial pressure of O2 using Dalton's Law of Partial Pressures, which states that the total pressure of a mixture of non-reacting gases is the sum of the partial pressures of the individual gases.
For example, if we have the mole fraction of O2 (let's call it X) and the total pressure of the system (let's call it P_total), we can calculate the partial pressure of O2 (P_O2) using the equation:
P_O2 = X * P_total
Without the composition of the mixture or the total pressure, we cannot determine the partial pressure of O2. Please provide more information for a specific calculation.