In the discussion regarding the equation H2 + 2O2 = 2HNO2, it is clarified that the partial pressures of H2 and O2 cannot simply be added to determine the partial pressure of the product, 2HNO2. The partial pressures of gases in a mixture must adhere to Dalton's Law, which states that the total pressure is the sum of the partial pressures and cannot exceed the total pressure of the system. Since the partial pressures of H2 and O2 are 0.5 and 0.3, respectively, their sum is already 0.8, leaving no room for the partial pressure of the product. Additionally, there is confusion regarding the presence of nitrogen in the reaction, which is not accounted for in the initial question. Therefore, the partial pressure of 2HNO2 cannot be 0.8 under these conditions.
