The Mobility of 02+ and O4+ Ions in Oxygen and the Equilibrium Constant for the Reaction O2++2O2? O4++02 at 273 and 294 K

The zero-field mobilities of oxygen ions in oxygen have been measured by the Bradbury-Nielsen time-of-flight method at temperatures of 194, 273 and 294 K and at pressures in the range 0�1-3�5kPa. The zero-field reduced mobilities of 0; and 0: have been determined to be 2�248�0�015 and 2'077�0'014cm2 s-1 V-1 at both 273 and 294K. The thermal equilibrium constant for the reaction 0; +02 +02 ;:t 0: +02 , obtained by fitting to the variation of the mobility with gas pressure, was found to be (3�4�0� 5) x 10-17 and (1�2�0�2) x 10-17 cm3 at 273 and 294 K respectively.