2 KNO3 -> 2KNO2 +O2 An experimental setup was set up to produce O2 gas for the above reaction. The O2 gas obtained in the setup was collected on the water. The temperature of the environment where the experiment was carried out was 20oC and the pressure was measured as 103.66 kPa. As a result of the experiment, which was carried out with 85% efficiency, 21.1 L of O2 gas was obtained. The vapor pressure of water at the test temperature is 17.54 Torr. According to this, what is the mass of KNO3 that is initially disintegrated?