On the xenon-fluorine reactions☆

Abstract The rate of reaction between xenon and fluorine to form xenon difluoride was measured at 110°, 120° and 130°C. The experiments were performed using xenon to fluorine mole ratios 1:5, 1:10 and 1:20 with a total pressure amounting 33 atm. as measured at 22°C. Under these conditions the reaction is of zero order with respect to fluorine and of first order with respect to xenon. The corresponding activation energy is 22 kcal/mole. Furthermore the influence of ScF 3 , TiF 4 , VF 5 , CrF 5 , MnF 3 , FeF 3 , CoF 3 , NiF 2 and CuF 2 on the rate of reaction between xenon and fluorine was investigated at 120°C. Mole ratio xenon to fluorine was in this case 1:4·5 with the total pressure amounting 36 atm. as measured at 22°C. Among these fluorides nickel difluoride has the strongest catalytic effect. In its presence it is possible to synthetize xenon hexafluoride even at 120°C starting from the gaseous mixture with the mole ratio Xe:F 2 = 1:5. The activation energy for the formation of xenon difluoride in the presence of nickel difluoride is lowered to 14 kcal/mole. The influence of ScF 3 , FeF 3 , CoF 3 and CuF 2 on the rate of xenon-fluorine reaction is small. The change in reaction rates could be explained most probably in terms of larger reaction surface. In the presence of TiF 4 , VF 5 , CrF 5 and MnF 3 new complex or addition compounds are formed: 3XeF 2 .2TiF 4 , XeF 2 .VF 5 , XeF 2 .2CrF 4 and XeF 2 .MnF 4 . Their influence on the rate of the xenon-fluorine reaction is described.